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AVRDEM 2 PLUS
SAMPLE CODE
© 2004 -2008 Sure Electronics Inc.
DB-DP115_Ver1.0
AVRDEM 2 PLUS
SAMPLE CODE
Sample 1. Light LEDs Associated With PORTA................................................. 2
Sample 2. Make the Buzzer Beep ........................................................................ 3
Sample 3. Read Temperature from Built-in TWI Temperature Sensor............. 4
Sample 4. Transmit Data through the USART of ATMEGA16 ........................... 7
Sample 5. How to Display Information on 7-segment LEDs ............................. 9
Sample 6. How to Display Information on HD44780 LCD Module ...................11
Sample 7. LED Mode Code................................................................................. 22
Sample 8. Display Information on the LCD Module. ........................................ 33
© 2004 -2008 Sure Electronics Inc.
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SAMPLE CODE
Sample 1. Illuminate LEDs Associated With PORTA
This Sample will show you how to illuminate LEDs associated with PORTA of ATMEGA16
microcontroller. LEDs are connected with PORTA1-3. When those pins are set to low,
corresponding LED will be illuminated.
#include <avr/io.h>
#include <avr/delay.h>
#include <compat/deprecated.h>
#define en_led3
cbi(PORTA,PA0)
#define disen_led3 sbi(PORTA,PA0)
#define en_led4
cbi(PORTA,PA1)
#define disen_led4 sbi(PORTA,PA1)
#define en_led5
cbi(PORTA,PA2)
#define disen_led5 sbi(PORTA,PA2)
#define en_led6
cbi(PORTA,PA3)
#define disen_led6 sbi(PORTA,PA3)
int main( void )
{
DDRA=0xFF;
while(1)
{
en_led3;
en_led4;
en_led5;
en_led6;
_delay_ms(8000);
_delay_ms(8000);
// All PORTA is output port
disen_led3;
disen_led4;
disen_led5;
disen_led6;
_delay_ms(8000);
_delay_ms(8000);
}
}
DB-DP115_Ver1.0 _Page2
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
Sample 2. Make the Buzzer Beep
In this Sample, we will show how to make the speaker that connected to PORTD7 (OC2)
pin buzz.
Before starting this test, you should first connect a passive speaker to J2. The speaker is
connected to the collector of a NPN transistor built in ULN2003 chip. Base of the ULN2003
chip is driven by PORTD7 (OC2 Pin). When a PWM wave is applied on the PORTD7 pin,
the speaker will start buzzing.
#include
#include
#include
#include
#include
<stdint.h>
<avr/io.h>
<util/twi.h>
<avr/delay.h>
<compat/deprecated.h>
#define uchar unsigned char
#define uint unsigned int
#define FREQ 4
void DelayMs(uint ms)
{
uint i;
for(i=0;i<ms;i++)
_delay_loop_2(FREQ*250);
}
void PWM(uchar pwmduty)
{
TCCR2=_BV(WGM20)|_BV(COM21)|_BV(CS22); //CLK/64
TCNT2=0;
DDRD |= _BV(PD7);
OCR2=pwmduty;
DelayMs(100);
}
int main (void)
{
uint i=0;
while(1)
© 2004 -2008 Sure Electronics Inc.
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SAMPLE CODE
{
i++;
if(i%100==0)
PWM(4);
else
PWM(0);
}
}
Sample 3. Read Temperature from Built-in TWI Temperature Sensor
This Sample will show how to read temperature value from LM75A temperature sensor via
TWI interface of ATMEGA16 control microchip. In this demo code, only IIC operation of
ATMEGA16 control microchip is displayed.
LM75A is connected to PORTC0 and PORTC1. When correct time sequence has been
applied on those 2 pins, temperature data can be obtained from LM75A temperature
sensor.
#include <stdint.h>
#include <avr/io.h>
#include <util/twi.h>
#include <avr/delay.h>
#include <compat/deprecated.h>
#define uchar unsigned char
#define uint unsigned int
#define FREQ 4
#define TempRegAddr 0x00 // Address of Temperature sensor
#define ReadLM75Addr 0x91 // Device address is 0. Read
#define WriteLM75Addr 0x90 // Write
#define Twi_Stop() TWCR=_BV(TWINT)|_BV(TWSTO)|_BV(TWEN)
#define Twi_Start() TWCR=_BV(TWINT)|_BV(TWSTA)|_BV(TWEN)
#define check_TWINT() while(!(TWCR & (1<<TWINT))) // Wait for TWINT flag being set
uint cvalue,fvalue;
char cent_buf[6],fahr_buf[6];
DB-DP115_Ver1.0 _Page4
// Memory Centigrade and Fahrenheit value
// Centigrade and Fahrenheit value array
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
uchar TempHigh;
uchar TempLow;
uchar TempSign,TempData;
uchar TwiStatus;
void twi_init(void)
{
TWCR= 0X00; //disable twi
TWBR= 0x12; //set bit rate
TWSR= 0x01; //set prescale
TWCR= 0x04; //enable twi
}
void TWITempRead(uchar ReadDeviceAddr,uchar WriteDeviceAddr,uchar RegAddr)
{
uint j;
DelayMs(20);
while (TwiStatus != 0x08) // Check TWSR register. Clear the prescale bit.
{
Twi_Start();
// Send START signal
_delay_us(1);
TwiStatus=TWSR & 0xF8;
}
//StatusLihgting(0);
while (TwiStatus != 0x18)
// Check TWSR register. SLA+W signal has been
//sent, and ACK signal has been received.
{
TWDR = WriteDeviceAddr;
// Device Address (write)
TWCR=0x84;
_delay_us(1);
TwiStatus=TWSR & 0xF8;
}
while (TwiStatus != 0x28)
//DATA has been sent. ACK has been received
{
TWDR = RegAddr;
// Write LM75 address.
TWCR=0x84;
_delay_us(1);
TwiStatus=TWSR & 0xF8;
}
© 2004 -2008 Sure Electronics Inc.
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SAMPLE CODE
while (TwiStatus != 0x10)
//REPEATED START has been sent.
{
Twi_Start();
// Send REPEATED START
_delay_us(1);
TwiStatus=TWSR & 0xF8;
}
while (TwiStatus != 0x40)
// Check TWSR register. SLA+R has been sent.
//ACK has been received.
{
TWDR =ReadDeviceAddr;
TWCR=0x84;
_delay_us(1);
TwiStatus=TWSR & 0xF8;
// Device address
}
TwiStatus=0x00;
while (TwiStatus != 0x50)
// DATA has been received. ACK has been sent.
{
TWCR=0xc4;
// Receive high 8-bit data. ACK has been sent.
_delay_us(20);
TempHigh=TWDR;
TwiStatus=TWSR & 0xF8;
}
while(TwiStatus != 0x58)
//DATA has been received. NACK has been sent.
{
TwiStatus=TWSR & 0xF8;
TWCR=0x84;
// Receive low 8-bit data. nACK has been sent.
_delay_us(10);
TempLow=TWDR;
}
Twi_Stop();
// Send STOP
}
void LM75_Temperature(void)
{
unsigned int temp_H,temp_L;
TWITempRead(ReadLM75Addr,WriteLM75Addr,TempRegAddr);
temp_H=TempHigh;
//High bits
DB-DP115_Ver1.0 _Page6
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
temp_L=TempLow;
//Compute Centigrade
cvalue=(temp_H<<8)|temp_L;
cent_buf[0]=' ';
if((cvalue&0x80)==1)
{
cvalue=~cvalue+1;
cent_buf[0]='-';
}
cvalue=cvalue>>5;
cvalue=cvalue * 1.25;
cent_buf[1]=cvalue/100+48;
cent_buf[2]=(cvalue/10)%10+48;
cent_buf[3]='.';
cent_buf[4]=cvalue%10+48;
cent_buf[5]='\0';
//compute Fahrenheit
fvalue=((cvalue*9)/5)+32;
fahr_buf[0]=' ';
if((fvalue&0x80)==1)
{
fvalue=~fvalue+1;
fahr_buf[0]='-';
}
fahr_buf[1]=fvalue/100+48;
fahr_buf[2]=(fvalue/10)%10+48;
fahr_buf[3]='.';
fahr_buf[4]=fvalue%10+48;
fahr_buf[5]='\0';
//Low bits
//Calculate Base Complement
//Calculate Base Complement
}
Sample 4. Transmit Data through the USART of ATMEGA16
This Sample will show you how to transmit data through USART of ATMEGA16
microcontroller. User must configure Hyper Terminal or other terminal software in PC
© 2004 -2008 Sure Electronics Inc.
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SAMPLE CODE
correctly, and then connect this development board to PC.
A single-chip USB to UART Bridge CP2102 is connected to PORTD0/RXD, PORTD1/ TXD
of ATMEGA16 microcontroller.
#include <stdint.h>
#include <avr/io.h>
#include <avr/delay.h>
#define uchar unsigned char
#define uint unsigned int
uchar testuart[]={0x30,0x31,0x32,0x33};
void InitUsart(void)
//USART initializtion
{
DDRD=0xFE;
//PD0/RXD input, PD1/TXD output.
UCSRB=0x00;
UCSRA=0x00;
UBRRH=0x00;
UBRRL=0x0c;
// USART Baud Rate is 57600bps
UCSRC=((1<<URSEL)|(3<<UCSZ0))&(~_BV(USBS));
//Set frame format: 8data, 1stop bit
UCSRB=_BV(RXEN)|_BV(TXEN);
//Enable receiver and transmitter
}
void USART(uchar *sendbuf)
{
while((*sendbuf)!=0)
{
UDR = *(sendbuf++);
while(!(UCSRA & 0x40)) ;
UCSRA |= 0x40;
}
}
int main (void)
{
InitUsart();
while(1)
{
USART(testuart);
DB-DP115_Ver1.0 _Page8
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
_delay_ms(2000);
}
}
Sample 5. How to Display Information on 7-segment LEDs
This demonstration board shows how to display information on 7-segment LEDs through
GPIOs of ATMEGA16 microchip.
PORTB is connected to a-h pins of 7segment LEDs, and PORTA4-7 are connected to
ULN2003 chip, that drive 4 cathodes of those LEDs.
Remove the LCD panel above the LED segments.
Transmit data via PORTB and enable one of the cathodes, then the LED segments will
display a digit letter. If switch of cathode is quick enough, it will display 4 digits and looks
seamlessly.
#include <stdint.h>
#include <avr/io.h>
#include <avr/delay.h>
#include <compat/deprecated.h>
//Set LED common port
#define set_ledcom_port0 sbi(PORTA,PA7)
#define clr_ledcom_port0 cbi(PORTA,PA7)
#define set_ledcom_port1 sbi(PORTA,PA6)
#define clr_ledcom_port1 cbi(PORTA,PA6)
#define set_ledcom_port2 sbi(PORTA,PA5)
#define clr_ledcom_port2 cbi(PORTA,PA5)
#define set_ledcom_port3 sbi(PORTA,PA4)
#define clr_ledcom_port3 cbi(PORTA,PA4)
//Set LED data port
#define set_leddata0 sbi(PORTB,PB0)
#define set_leddata1 sbi(PORTB,PB1)
#define set_leddata2 sbi(PORTB,PB2
#define set_leddata3 sbi(PORTB,PB3)
#define set_leddata4 sbi(PORTB,PB4)
#define set_leddata5 sbi(PORTB,PB5)
#define set_leddata6 sbi(PORTB,PB6)
#define set_leddata7 sbi(PORTB,PB7)
© 2004 -2008 Sure Electronics Inc.
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SAMPLE CODE
#define clr_leddata0
#define clr_leddata1
#define clr_leddata2
#define clr_leddata3
#define clr_leddata4
#define clr_leddata5
#define clr_leddata6
#define clr_leddata7
cbi(PORTB,PB0)
cbi(PORTB,PB1)
cbi(PORTB,PB2
cbi(PORTB,PB3)
cbi(PORTB,PB4)
cbi(PORTB,PB5)
cbi(PORTB,PB6)
cbi(PORTB,PB7)
// Main Programmer
void main( void )
{
DDRB |= 0xf0;
// Make common port ouput
DDRB=0xff;
// Make data port ouput
while(1)
{
Clr_ledcom_port0;
Clr_ledcom_port1;
Clr_ledcom_port2;
set_ledcom_port 3;
CLR_LEDDATA0;
SET_LEDDATA1;
SET_LEDDATA2;
CLR_LEDDATA3;
CLR_LEDDATA4;
CLR_LEDDATA5;
CLR_LEDDATA6;
CLR_LEDDATA7;
Delay100TCYx(2);
Clr_ledcom_port0;
Clr_ledcom_port1;
set_ledcom_port 2;
Clr_ledcom_port3;
SET_LEDDATA0;
SET_LEDDATA1;
CLR_LEDDATA2;
SET_LEDDATA3;
SET_LEDDATA4;
CLR_LEDDATA5;
SET_LEDDATA6;
CLR_LEDDATA7;
Delay100TCYx(2);
Clr_ledcom_port0;
set_ledcom_port 1;
Clr_ledcom_port2;
DB-DP115_Ver1.0 _Page10
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
Clr_ledcom_port3;
SET_LEDDATA0;
SET_LEDDATA1;
SET_LEDDATA2;
SET_LEDDATA3;
CLR_LEDDATA4;
CLR_LEDDATA5;
SET_LEDDATA6;
CLR_LEDDATA7;
Delay100TCYx(2);
set_ledcom_port 0;
Clr_ledcom_port1;
Clr_ledcom_port2;
Clr_ledcom_port3;
CLR_LEDDATA0;
SET_LEDDATA1;
SET_LEDDATA2;
CLR_LEDDATA3;
CLR_LEDDATA4;
SET_LEDDATA5;
SET_LEDDATA6;
CLR_LEDDATA7;
Delay100TCYx(2);
}
}
Sample 6. How to Display Information on HD44780 LCD Module
This Sample will show you how to display information on HD44780 compatible LCD Module.
The LCD module is connected to PORTB (as data port), PORTD4 (E signal of LCD module),
PORTD3 (RW signal of LCD module), and PORTD2 (RS signal of LCD module). Before
using this function, you should install the LCD panel with screws. Adjust R28 to change the
contrast of the LCD panel.
#include <stdint.h>
#include <avr/io.h>
#include <util/twi.h>
#include <avr/delay.h>
#include <compat/deprecated.h>
#include <avr/interrupt.h>
#include <avr/hd44780.h>
#define uchar unsigned char
© 2004 -2008 Sure Electronics Inc.
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SAMPLE CODE
#define uint unsigned int
char LCD_name[]="Sure Electronics";
char LCD_Ver[]="Ver1.0";
void InitPort(void)
{
DDRB=0xFF;
DDRD=0xFE;
}
// All PORTB is output port
/************* LCD ************************************ Beginning *******************************/
/* DATA_PORT defines the port to which the LCD data lines are connected */
#define DATA_PORT
PORTB
#define DATA_PIN
PINB
#define TRIS_DATA_PORT DDRB
/* CTRL_PORT defines the port where the control lines are connected.
* These are just samples, change to match your application.
*/
#define SET_RW_PIN sbi(PORTD,PD3) /* PORT for RW, RW=1 */
#define CLR_RW_PIN cbi(PORTD,PD3)
/* RW=0 */
#define SET_TRIS_RW sbi(DDRD,DDD3)
/* TRIS for RW */
#define CLR_TRIS_RW cbi(DDRD,DDD3)
/* TRIS for RW */
#define SET_RS_PIN sbi(PORTD,PD2) /* PORT for RS, RS=1 */
#define CLR_RS_PIN cbi(PORTD,PD2) /* PORT for RS, RS=0 */
#define SET_TRIS_RS sbi(DDRD,DDD2)
/* TRIS for RS */
#define CLR_TRIS_RS cbi(DDRD,DDD2)
/* TRIS for RS */
#define SET_E_PIN
sbi(PORTD,PD4) /* PORT for E ,1 */
#define CLR_E_PIN
cbi(PORTD,PD4) /* PORT for E ,0 */
#define SET_TRIS_E sbi(DDRD,DDD4)
/* TRIS for E */
#define CLR_TRIS_E cbi(DDRD,DDD4)
/* TRIS for E */
/* Display ON/OFF Control defines */
#define DON
0b00001111 /* Display on
*/
#define DOFF
0b00001011 /* Display off
*/
#define CURSOR_ON 0b00001111 /* Cursor on
*/
#define CURSOR_OFF 0b00001101 /* Cursor off
*/
#define BLINK_ON
0b00001111 /* Cursor Blink
*/
#define BLINK_OFF 0b00001110 /* Cursor No Blink */
/* Cursor or Display Shift defines */
#define SHIFT_CUR_LEFT
0b00010011
#define SHIFT_CUR_RIGHT 0b00010111
#define SHIFT_DISP_LEFT 0b00011011
#define SHIFT_DISP_RIGHT 0b00011111
/* Cursor shifts to the left */
/* Cursor shifts to the right */
/* Display shifts to the left */
/* Display shifts to the right */
/* Function Set defines */
DB-DP115_Ver1.0 _Page12
© 2004 -2008 Sure Electronics Inc.
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SAMPLE CODE
#define EIGHT_BIT 0b00111111 /* 8-bit Interface
*/
#define LINES_5X7 0b00111011 /* 5x7 characters, multiple line */
#define PARAM_SCLASS auto
#define MEM_MODEL far /* Change this to near for small memory model */
/* OpenXLCD
* Configures I/O pins for external LCD
*/
void OpenXLCD(uchar);
/* SetCGRamAddr
* Sets the character generator address
*/
void SetCGRamAddr(uchar);
/* SetDDRamAddr
* Sets the display data address
*/
void SetDDRamAddr(uchar);
/* BusyXLCD
* Returns the busy status of the LCD
*/
uchar BusyXLCD(void);
/* ReadAddrXLCD
* Reads the current address
*/
uchar ReadAddrXLCD(void);
/* ReadDataXLCD
* Reads a byte of data
*/
char ReadDataXLCD(void);
/* WriteCmdXLCD
* Writes a command to the LCD
*/
void WriteCmdXLCD(uchar);
/* WriteDataXLCD
* Writes a data byte to the LCD
*/
void WriteDataXLCD(char);
/* putcXLCD
* A putc is a write
*/
© 2004 -2008 Sure Electronics Inc.
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SAMPLE CODE
#define putcXLCD WriteDataXLCD
/* putsXLCD
* Writes a string of characters to the LCD
*/
void putsXLCD(char *);
/* putrsXLCD
* Writes a string of characters in ROM to the LCD
*/
void putsXLCD(char *buffer);
/********************************************************************
*
Function Name: BusyXLCD
*
*
Return Value: char: busy status of LCD controller
*
*
Parameters:
void
*
*
Description:
This routine reads the busy status of the *
*
Hitachi HD44780 LCD controller.
*
********************************************************************/
uchar BusyXLCD(void)
{
SET_RW_PIN;
// Set the control bits for read BF
CLR_RS_PIN;
_delay_us(10);
SET_E_PIN;
// Clock in the command
_delay_us(10);
if(DATA_PIN&0x80)
// Read bit 7 (busy bit)
{
// If high
CLR_E_PIN;
// Reset clock line
CLR_RW_PIN;
// Reset control line
return 1;
// Return TRUE
}
else
// Bit 7 low
{
CLR_E_PIN;
// Reset clock line
CLR_RW_PIN;
// Reset control line
return 0;
// Return FALSE
}
}
/********************************************************************
*
Function Name: OpenXLCD
*
Return Value: void
*
*
Parameters:
lcdtype: sets the type of LCD (lines)
*
*
Description:
This routine configures the LCD. Based on *
*
the Hitachi HD44780 LCD controller. The
*
*
routine will configure the I/O pins of the *
*
microcontroller, setup the LCD for 4- or
*
DB-DP115_Ver1.0 _Page14
*
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
*
8-bit mode and clear the display. The user *
*
must provide three delay routines:
*
*
DelayFor18TCY() provides a 18 Tcy delay
*
*
DelayPORXLCD() provides at least 15ms delay *
*
DelayXLCD() provides at least 5ms delay
*
********************************************************************/
void OpenXLCD(uchar lcdtype)
{
// The data bits are made into inputs
DATA_PIN = 0;
TRIS_DATA_PORT = 0x00;
SET_TRIS_RW;
SET_TRIS_RS;
SET_TRIS_E;
CLR_RW_PIN;
CLR_RS_PIN;
CLR_E_PIN;
// All control signals made outputs
// R/W pin made low
// Register select pin made low
// Clock pin made low
// Delay for more than 15ms to allow for LCD Power on reset
_delay_ms(16);
// Setup interface to LCD
DATA_PORT = 0;
TRIS_DATA_PORT = 0xff;
DATA_PORT = 0b00110000;
CLR_RW_PIN;
CLR_RS_PIN;
SET_E_PIN;
_delay_us(10);
CLR_E_PIN;
// Data port output
// Function set cmd(8-bit interface)
// R/W pin made low
// Register select pin made low
// Clock the cmd in
// Delay for at least 4.1ms
_delay_ms(6);
// Setup interface to LCD
DATA_PORT = 0;
DATA_PORT = 0b00110000;
CLR_RW_PIN;
CLR_RS_PIN;
SET_E_PIN;
_delay_us(10);
CLR_E_PIN;
// Function set cmd(8-bit interface)
// R/W pin made low
// Register select pin made low
// Clock the cmd in
// Delay for at least 100us
© 2004 -2008 Sure Electronics Inc.
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_delay_ms(1);
// Setup interface to LCD
DATA_PORT = 0;
DATA_PORT = 0b00110000;
SET_E_PIN;
_delay_us(10);
CLR_E_PIN;
TRIS_DATA_PORT = 0x00;
// Function set cmd(8-bit interface)
// Clock cmd in
// Make data port input
// Set data interface width, # lines, font
while(BusyXLCD());
// Wait if LCD busy
WriteCmdXLCD(lcdtype);
// Function set cmd
// Turn the display on then off
while(BusyXLCD());
// Wait if LCD busy
WriteCmdXLCD(DOFF);
// Display OFF/Blink OFF
while(BusyXLCD());
// Wait if LCD busy
WriteCmdXLCD(DON);
// Display ON/Blink ON
while(BusyXLCD());
// Wait if LCD busy
WriteCmdXLCD(BLINK_ON&CURSOR_ON);
// Display ON/Blink ON
// Clear display
while(BusyXLCD());
WriteCmdXLCD(0x01);
// Wait if LCD busy
// Clear display
// Set entry mode inc, no shift
while(BusyXLCD());
// Wait if LCD busy
WriteCmdXLCD(SHIFT_CUR_LEFT); // Entry Mode
while(BusyXLCD());
WriteCmdXLCD(0b00000110);
// Set DD Ram address to 0
while(BusyXLCD());
SetDDRamAddr(0b00000111);
// Wait if LCD busy
// Set Display data ram address
to 0
return;
}
/********************************************************************
*
Function Name: putrsXLCD
*
Return Value: void
DB-DP115_Ver1.0 _Page16
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
*
Parameters:
buffer: pointer to string
*
Description:
This routine writes a string of bytes to the
*
Hitachi HD44780 LCD controller. The user
*
must check to see if the LCD controller is
*
busy before calling this routine. The data
*
is written to the character generator RAM or
*
the display data RAM depending on what the
*
previous SetxxRamAddr routine was called.
********************************************************************/
/*
void putrsXLCD(const rom char *buffer)
{
while(*buffer)
// Write data to LCD up to null
{
while(BusyXLCD());
// Wait while LCD is busy
WriteDataXLCD(*buffer); // Write character to LCD
buffer++;
// Increment buffer
}
return;
}
*/
/********************************************************************
*
Function Name: putsXLCD
*
Return Value: void
*
Parameters:
buffer: pointer to string
*
Description:
This routine writes a string of bytes to the
*
Hitachi HD44780 LCD controller. The user
*
must check to see if the LCD controller is
*
busy before calling this routine. The data
*
is written to the character generator RAM or
*
the display data RAM depending on what the
*
previous SetxxRamAddr routine was called.
********************************************************************/
void putsXLCD(char *buffer)
{
while(*buffer)
// Write data to LCD up to null
{
while(BusyXLCD()) ;
// Wait while LCD is busy
WriteDataXLCD(*buffer); // Write character to LCD
buffer++;
// Increment buffer
}
return;
}
/*********************************************************************
*
Function Name: ReadAddrXLCD
*
Return Value: char: address from LCD controller
© 2004 -2008 Sure Electronics Inc.
*
*
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*
Parameters:
void
*
*
Description:
This routine reads an address byte from the *
*
Hitachi HD44780 LCD controller. The user
*
*
must check to see if the LCD controller is *
*
busy before calling this routine. The address*
*
is read from the character generator RAM or *
*
the display data RAM depending on what the *
*
previous SetxxRamAddr routine was called.
*
*********************************************************************/
uchar ReadAddrXLCD(void)
{
char data;
// Holds the data retrieved from the LCD
SET_RW_PIN;
CLR_RS_PIN;
_delay_us(10);
SET_E_PIN;
_delay_us(10);
data = DATA_PIN;
CLR_E_PIN;
CLR_RW_PIN;
return (data&0x7f);
// Set control bits for the read
// Clock data out of the LCD controller
// Save the data in the register
// Reset the control lines
// Return the address, Mask off the busy bit
}
/********************************************************************
*
Function Name: ReadDataXLCD
*
Return Value: char: data byte from LCD controller
*
*
Parameters:
void
*
*
Description:
This routine reads a data byte from the
*
*
Hitachi HD44780 LCD controller. The user
*
*
must check to see if the LCD controller is *
*
busy before calling this routine. The data *
*
is read from the character generator RAM or *
*
the display data RAM depending on what the *
*
previous SetxxRamAddr routine was called. *
********************************************************************/
char ReadDataXLCD(void)
{
char data;
SET_RS_PIN;
SET_RW_PIN;
_delay_us(10);
DB-DP115_Ver1.0 _Page18
*
// Set the control bits
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
SET_E_PIN;
_delay_us(10);
data = DATA_PIN;
CLR_E_PIN;
CLR_RS_PIN;
CLR_RW_PIN;
CLR_E_PIN;
_delay_us(10);
SET_E_PIN;
_delay_us(10);
CLR_E_PIN;
CLR_RS_PIN;
CLR_RW_PIN;
return(data);
// Clock the data out of the LCD
// Read the data
// Reset the control bits
// Reset the clock line
// Clock the next nibble out of the LCD
// Reset the control bits
// Return the data byte
}
/********************************************************************
*
Function Name: SetCGRamAddr
*
*
Return Value: void
*
*
Parameters:
CGaddr: character generator ram address
*
*
Description:
This routine sets the character generator *
*
address of the Hitachi HD44780 LCD
*
*
controller. The user must check to see if *
*
the LCD controller is busy before calling *
*
this routine.
*
********************************************************************/
void SetCGRamAddr(uchar CGaddr)
{
TRIS_DATA_PORT = 0xff;
// Make data port ouput
DATA_PORT = CGaddr | 0b01000000;
// Write cmd and address to port
CLR_RW_PIN;
// Set control signals
CLR_RS_PIN;
_delay_us(10);
SET_E_PIN;
// Clock cmd and address in
_delay_us(10);
CLR_E_PIN;
_delay_us(10);
TRIS_DATA_PORT = 0x00;
// Make data port inputs
return;
}
/********************************************************************
*
Function Name: SetDDRamAddr
© 2004 -2008 Sure Electronics Inc.
*
DB-DP115_Ver1.0_Page19
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SAMPLE CODE
*
Return Value: void
*
*
Parameters:
CGaddr: display data address
*
*
Description:
This routine sets the display data address *
*
of the Hitachi HD44780 LCD controller. The *
*
user must check to see if the LCD controller*
*
is busy before calling this routine.
*
********************************************************************/
void SetDDRamAddr(uchar DDaddr)
{
TRIS_DATA_PORT = 0xff;
// Make port output
DATA_PORT = DDaddr | 0b10000000;
// Write cmd and address to port
CLR_RW_PIN;
// Set the control bits
CLR_RS_PIN;
_delay_us(10);
SET_E_PIN;
// Clock the cmd and address in
_delay_us(10);
CLR_E_PIN;
_delay_us(10);
TRIS_DATA_PORT = 0;
// Make port input
return;
}
/********************************************************************
*
Function Name: WriteCmdXLCD
*
*
Return Value: void
*
*
Parameters:
cmd: command to send to LCD
*
*
Description:
This routine writes a command to the Hitachi*
*
HD44780 LCD controller. The user must check *
*
to see if the LCD controller is busy before *
*
calling this routine.
*
********************************************************************/
void WriteCmdXLCD(uchar cmd)
{
TRIS_DATA_PORT = 0xff;
// Data port output
DATA_PORT = 0;
DATA_PORT |= cmd;
// Write command to data port
CLR_RW_PIN;
// Set the control signals
CLR_RS_PIN;
// for sending a command
_delay_us(10);
SET_E_PIN;
// Clock the command in
_delay_us(10);
CLR_E_PIN;
_delay_us(10);
TRIS_DATA_PORT = 0x00;
// Data port input
return;
}
DB-DP115_Ver1.0 _Page20
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
/************************************************************************************
*
Function Name: WriteDataXLCD
*
*
Return Value: void
*
*
Parameters:
data: data byte to be written to LCD
*
*
Description:
This routine writes a data byte to the
*
*
Hitachi HD44780 LCD controller. The user
*
*
must check to see if the LCD controller is
*
*
busy before calling this routine. The data
*
*
is written to the character generator RAM or *
*
the display data RAM depending on what the *
*
previous SetxxRamAddr routine was called. *
*************************************************************************************/
void WriteDataXLCD(char data)
{
TRIS_DATA_PORT = 0xff;
// Make port output
DATA_PORT = data;
// Write data to port
SET_RS_PIN;
// Set control bits
CLR_RW_PIN;
_delay_us(10);
SET_E_PIN;
// Clock data into LCD
_delay_us(10);
CLR_E_PIN;
CLR_RS_PIN;
// Reset control bits
TRIS_DATA_PORT = 0x00;
// Make port input
return;
}
/************** LCD ************************************** END *********************************/
int main (void)
{
uchar i;
char display_name[]="Sure Electronics";
char display_Ver[]="Ver 2.1";
InitPort();
InitLCD();
// Configure external LCD
OpenXLCD( EIGHT_BIT&LINES_5X7 );
// Write to LCD
while(BusyXLCD());
putsXLCD(display_name);
// Wait if LCD busy
// Write to LCD
while(BusyXLCD());
SetDDRamAddr(0x40);
// Wait if LCD busy
© 2004 -2008 Sure Electronics Inc.
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SAMPLE CODE
putsXLCD(display_Ver);
while(1){};
}
Sample 7. LED Mode Code
This demonstration shows how to display message on 7segment LEDs through GPIOs of
ATMEGA16 microcontroller.
The 8 bits data output of PORTB is connected to a-h of 7segment LEDs and PORTA4-7 is
connected to base of ULN2003, then drive 4 cathode of those LEDs. Remove the LCD
panel on the LED segments. Send data from PORTB and enable one of the cathodes. The
LED segments will display a digit. If switch-on and switch-off of the four cathodes can be
turned quickly enough, it will display 4 digits just like simultaneously. That looks seamlessly.
#include <stdint.h>
#include <avr/io.h>
#include <util/twi.h>
#include <avr/delay.h>
#include <compat/deprecated.h>
#include <avr/interrupt.h>
#define uchar unsigned char
#define uint unsigned int
#define FREQ 4
#define TempRegAddr 0x00 // Address of Temperature sensor
#define ReadLM75Addr 0x91 // Device address is 0. Read
#define WriteLM75Addr 0x90 // Write
#define Twi_Stop() TWCR=_BV(TWINT)|_BV(TWSTO)|_BV(TWEN)
#define Twi_Start() TWCR=_BV(TWINT)|_BV(TWSTA)|_BV(TWEN)
#define check_TWINT() while(!(TWCR & (1<<TWINT))) // Wait for TWINT flag being set
#define leddata_port PORTB
#define set_ledcom_port0 sbi(PORTA,PA7)
#define clr_ledcom_port0 cbi(PORTA,PA7)
#define set_ledcom_port1 sbi(PORTA,PA6)
#define clr_ledcom_port1 cbi(PORTA,PA6)
#define set_ledcom_port2 sbi(PORTA,PA5)
#define clr_ledcom_port2 cbi(PORTA,PA5)
#define set_ledcom_port3 sbi(PORTA,PA4)
DB-DP115_Ver1.0 _Page22
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AVRDEM 2 PLUS
SAMPLE CODE
#define clr_ledcom_port3 cbi(PORTA,PA4)
#define en_led3
cbi(PORTA,PA0)
#define disen_led3 sbi(PORTA,PA0)
#define en_led4
cbi(PORTA,PA1)
#define disen_led4 sbi(PORTA,PA1)
#define en_led5
cbi(PORTA,PA2)
#define disen_led5 sbi(PORTA,PA2)
#define en_led6 cbi(PORTA,PA3)
#define disen_led6 sbi(PORTA,PA3)
#define Func_key (PINC&0x80)
#define Change_key (PINC&0x40)
// Function key
// Switch key
uint cvalue,fvalue;
// Memory Centigrade and Fahrenheit value
char cent_buf[6],fahr_buf[6];
// Centigrade and Fahrenheit value array
uchar reset_key_pressed,last_reset_key_pressed;
uchar Func_key_pressed,last_Func_key_pressed;
uchar change_key_pressed,last_change_key_pressed;
uchar LED_thousand,LED_hundred,LED_ten,LED_one;
uchar value_thousand,value_hundred,value_ten,value_one;
uchar temperature_flag;
uchar cnt_fuckey;
uchar key_flag=0;
char pointer=0;
uchar TempHigh;
uchar TempLow;
uchar TempSign,TempData;
uchar TwiStatus;
const uchar Digital_TAB[]=
{0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,
0x6d,0x1c,0x50,0x79,0x86,0x06};
// 0123456789 SurE 1.1
char Cent[]="Centigrade";
char Fahr[]="Fahrenheit";
char Current[]="Current Temperatrue";
void InitPort(void);
void InitUsart(void);
void InitTwi(void);
void InitDevice(void);
void DelayMs(uint ms);
void PWM(uchar pwmduty);
char Funckey(void);
void ChangeKey(void);
void LED_InitData(void);
void LED_Data(uint data);
© 2004 -2008 Sure Electronics Inc.
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SAMPLE CODE
void LED_Display(uchar num);
void TWITempRead(uchar ReadDeviceAddr,uchar WriteDeviceAddr,uchar RegAddr) ;
void LM75_Temperature(void);
void USART(char *sendbuf);
/*********** Initializtion ************************************* Beginning ***********************/
void InitPort(void)
{
ACSR &=0x7f;
DDRA=0xFF;
DDRB=0xFF;
DDRC=0x3C;
// Close Comparator
// All PortA is output port
// All PORTB is output port
// PC7 is for Switch SW1 Input
// PC6 is for Switch SW2 Input
//PC0,PC1 is for TWI
PORTC |=_BV(PORTC6)|_BV(PORTC7)|_BV(PORTC0)|_BV(PORTC1);
SFIOR&=~_BV(PUD);
DDRD=0xFE;
}
void InitUsart(void)
{
UCSRB=0x00;
UCSRA=0x00;
UBRRH=0x00;
UBRRL=0x0c;
// USART Baud Rate is 57600bps
UCSRC=((1<<URSEL)|(3<<UCSZ0))&(~_BV(USBS));
//Set frame format: 8data, 1stop bit
UCSRB=_BV(RXEN)|_BV(TXEN);
//Enable receiver and transmitter
}
void InitDevice(void)
{
cli();
InitPort();
InitUsart();
}
/*********** Initializtion ************************************* END ***********************/
/*********** PWM ******************************* Beginning ******************************/
void DelayMs(uint ms)
{
uint i;
for(i=0;i<ms;i++)
_delay_loop_2(FREQ*250);
}
DB-DP115_Ver1.0 _Page24
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AVRDEM 2 PLUS
SAMPLE CODE
void PWM(uchar pwmduty)
{
TCCR2=_BV(WGM20)|_BV(COM21)|_BV(CS22);
TCNT2=0;
DDRD |= _BV(PD7);
OCR2=pwmduty;
DelayMs(100);
}
//CLK/64
/*********** PWM ******************************* END ******************************/
/*********** Scan key status ******************************* Beginning *******************/
char Funckey(void)
{
uchar temp;
if(Func_key==0x80)
Func_key_pressed=1;
else if(Func_key==0)
Func_key_pressed=0;
if((Func_key_pressed==0)&(last_Func_key_pressed==1))
{
_delay_ms(1);
if(Func_key_pressed==0)cnt_fuckey++;
}
last_Func_key_pressed=Func_key_pressed;
temp=cnt_fuckey%4;
return temp;
}
/*********** Scan key status ******************************* END ******************************/
/*********** LED data and display******************************* Beginning ******************/
void LED_InitData(void)
{
uchar i,j;
uchar temp;
while(1)
{
i++;
j=i%4;
LED_Display(j);
//Display Characters
if(i==1)
{
temp++;
if(temp==2)
© 2004 -2008 Sure Electronics Inc.
//Display "Sure" when Power on or after Resetting
DB-DP115_Ver1.0_Page25
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SAMPLE CODE
{
value_thousand=0x6d;
value_hundred=0x1c;
value_ten=0x50;
value_one=0x79;
}
if(temp==120)
{
value_thousand=0x00;
value_hundred=0x00;
value_ten=0x86;
value_one=0x06;
}
//Then Display "1.1" at some Intervals
}
if(temp==255)break;
}
}
void LED_Data(uint data)
{
uint i;
LED_thousand=0;
LED_hundred=0;
LED_ten=0;
LED_one=0;
for(i=0;i<data;i++)
//Data is divided into four digits
{
LED_one++;
if(LED_one>=10){LED_one=0;LED_ten++;}
if(LED_ten>=10){LED_ten=0;LED_hundred++;}
if(LED_hundred>=10){LED_hundred=0;LED_thousand++;}
}
for(i=0;i<10;i++)
// Compute which digit to display on corresponding position
{
if(i==LED_thousand){value_thousand=Digital_TAB[i];}
if(i==LED_hundred){value_hundred=Digital_TAB[i];}
if(i==LED_ten){value_ten=Digital_TAB[i];}
if(i==LED_one){value_one=Digital_TAB[i];}
}
if(temperature_flag==1)
{
value_ten=value_ten|0x80; // Temperature value should have a decimal point
temperature_flag=0;
}
if((cent_buf[0]=='-')|(fahr_buf[0]=='-'))
{
value_thousand=0x64;
}
DB-DP115_Ver1.0 _Page26
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
}
void LED_Display(uchar num)
{
clr_ledcom_port0;
clr_ledcom_port1;
clr_ledcom_port2;
clr_ledcom_port3;
switch(num)
{
case(0):
{
set_ledcom_port3;
leddata_port=value_thousand;
}break;
case(1):
{
set_ledcom_port2;
leddata_port=value_hundred;
}break;
case(2):
{
set_ledcom_port1;
leddata_port=value_ten;
}break;
case(3):
{
set_ledcom_port0;
leddata_port=value_one;
}break;
}
//Display Top Digit
//Display Second-order Digit
//Display Third-order Digit
//Display Least Significant Digit
}
/*********** LED data and display******************************* END *****************/
/*********** TWI operation routine ********************** Beginning **********************/
void InitTwi(void)
{
TWCR= 0X00; //disable twi
TWBR= 0x12; //set bit rate
TWSR= 0x01; //set prescale
TWCR= 0x04; //enable twi
}
void TWITempRead(uchar ReadDeviceAddr,uchar WriteDeviceAddr,uchar RegAddr)
{
while (TwiStatus != 0x08) // Check TWSR register. Clear the prescale bit.
© 2004 -2008 Sure Electronics Inc.
DB-DP115_Ver1.0_Page27
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SAMPLE CODE
{
Twi_Start();
// Send START signal
_delay_us(1);
TwiStatus=TWSR & 0xF8;
}
//StatusLihgting(0);
while (TwiStatus != 0x18)
// Check TWSR register. SLA+W signal has been
//sent, and ACK signal has been received.
{
TWDR = WriteDeviceAddr;
TWCR=0x84;
_delay_us(1);
TwiStatus=TWSR & 0xF8;
// Device Address (write)
}
while (TwiStatus != 0x28)
//DATA has been sent. ACK has been received
{
TWDR = RegAddr;
// Write LM75 address.
TWCR=0x84;
_delay_us(1);
TwiStatus=TWSR & 0xF8;
}
while (TwiStatus != 0x10)
//REPEATED START has been sent.
{
Twi_Start();
// Send REPEATED START
_delay_us(1);
TwiStatus=TWSR & 0xF8;
}
while (TwiStatus != 0x40)
// Check TWSR register. SLA+R has been sent.
//ACK has been received.
{
TWDR =ReadDeviceAddr;
// Device address
TWCR=0x84;
_delay_us(1);
TwiStatus=TWSR & 0xF8;
}
TwiStatus=0x00;
while (TwiStatus != 0x50)
// DATA has been received. ACK has been sent.
{
TWCR=0xc4;
// Receive high 8-bit data. ACK has been sent.
DB-DP115_Ver1.0 _Page28
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AVRDEM 2 PLUS
SAMPLE CODE
_delay_us(20);
TempHigh=TWDR;
TwiStatus=TWSR & 0xF8;
}
while(TwiStatus != 0x58)
//DATA has been received. NACK has been sent.
{
TwiStatus=TWSR & 0xF8;
TWCR=0x84;
// Receive low 8-bit data. nACK has been sent.
_delay_us(10);
TempLow=TWDR;
}
Twi_Stop();
// Send STOP
}
/*********** TWI operation routine ******************************** END ****************/
/*********** LM75 Read routine ************************************* Beginning ***********/
void LM75_Temperature(void)
//Read temperature value by LM75 temperature sensor
{
uint temp_H,temp_L;
TWITempRead(ReadLM75Addr,WriteLM75Addr,TempRegAddr);
temp_H=TempHigh;
temp_L=TempLow;
//Compute Centigrade
cvalue=(temp_H<<8)|temp_L;
cent_buf[0]=' ';
if((cvalue&0x80)==1)
{
cvalue=~cvalue+1;
cent_buf[0]='-';
}
cvalue=cvalue>>5;
cvalue=cvalue * 1.25;
cent_buf[1]=cvalue/100+48;
cent_buf[2]=(cvalue/10)%10+48;
cent_buf[3]='.';
cent_buf[4]=cvalue%10+48;
cent_buf[5]='\0';
//High bits
//Low bits
//Calculate Base Complement
//compute Fahrenheit
fvalue=((cvalue*9)/5)+32;
fahr_buf[0]=' ';
© 2004 -2008 Sure Electronics Inc.
DB-DP115_Ver1.0_Page29
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SAMPLE CODE
if((fvalue&0x80)==1)
{
fvalue=~fvalue+1;
fahr_buf[0]='-';
}
fahr_buf[1]=fvalue/100+48;
fahr_buf[2]=(fvalue/10)%10+48;
fahr_buf[3]='.';
fahr_buf[4]=fvalue%10+48;
fahr_buf[5]='\0';
//Calculate Base Complement
}
/*********** LM75 Read routine ************************************* END ***********************/
/*********** USART ************************************* Beginning ***********************/
void USART(char *sendbuf)
{
while ((*sendbuf)!=0)
{
UDR = *(sendbuf++);
while(!(UCSRA & 0x40)) ;
UCSRA |= 0x40;
}
}
/*********** USART ************************************* END ***********************/
/*********** Interrupt service routine *************************** Beginning *************/
SIGNAL(SIG_OVERFLOW0)
{
uchar isr_cyc_cnt,key_data;
uint temp;
uint uart_cnt;
char Cent[]="Centigrade";
char Fahr[]="Fahrenheit";
char Current[]="Current Temperatrue";
TCNT0 = 0xda;
// Reload counter value
isr_cyc_cnt++;
if(isr_cyc_cnt>4)isr_cyc_cnt=0; // Not more than 4-digit data
switch(isr_cyc_cnt)
{
case(0):
{
LED_Display(0);
//Display Characters
}break;
case(1):
DB-DP115_Ver1.0 _Page30
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
{
LED_Display(1);
}break;
case(2):
{
LED_Display(2);
}break;
case(3):
{
LED_Display(3);
}break;
case(4):
{
clr_ledcom_port0;
clr_ledcom_port1;
clr_ledcom_port2;
clr_ledcom_port3;
uart_cnt++;
if((uart_cnt&0xff) == 0xff)
{
USART(Current);
UDR=13;
UDR=10;
//Display Characters
//Display Characters
//Display Characters
USART(cent_buf);
USART(Cent);
UDR=13;
UDR=10;
USART(fahr_buf);
USART(Fahr);
UDR=13;
UDR=10;
}
else
LM75_Temperature();
//Read Temperature Value
}break;
}
if(key_flag==0)
//Display one piece of information at a time
{
key_data=Funckey();
switch(key_data)
{
case(1):
//Display "Sure"
{
value_thousand=0x6d;
value_hundred=0x1c;
© 2004 -2008 Sure Electronics Inc.
DB-DP115_Ver1.0_Page31
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SAMPLE CODE
value_ten=0x50;
value_one=0x79;
}break;
case(2):
//Display "1.1"
{
value_thousand=0x00;
value_hundred=0x00;
value_ten=0x86;
value_one=0x06;
}break;
case(3):
//Display Centigrade Value
{
temperature_flag=1;
LED_Data(cvalue);
}break;
case(0):
//Display Fahrenheit Value
{
temperature_flag=1;
LED_Data(fvalue);
}break;
}
if(Change_key==0)key_flag=1;
}
if(key_flag==1)
//Display information in turn
{
temp++;
if(temp%512==127)
//Display "Sure"
{
value_thousand=0x6d;
value_hundred=0x1c;
value_ten=0x50;
value_one=0x79;
}
if(temp%512==255)
//Display "1.1"
{
value_thousand=0x00;
value_hundred=0x00;
value_ten=0x86;
value_one=0x06;
}
if(temp%512==383)
//Display Centigrade Value
{
temperature_flag=1;
LED_Data(cvalue);
}
if(temp%512==0)
//Display Fahrenheit Value
{
temperature_flag=1;
DB-DP115_Ver1.0 _Page32
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SAMPLE CODE
LED_Data(fvalue);
}
if(Func_key==0)key_flag=0;
}
}
/********** Interrupt service routine ********************************** END ********************/
int main (void)
{
InitDevice();
InitTwi();
LED_InitData();
_delay_ms(10);
TCNT0=0;
TCCR0=5;
TIMSK=_BV(TOIE0);
sei();
//prescale: ck/1024
while(1) ;
}
Sample 8. Display Information on the LCD Module.
This Sample shows how to display information on the HD44780 compatible LCD Module.
The LCD module was connected to PORTB (as data port), PORTD4 (E signal of LCD
module), PORTD3 (RW signal of LCD module), and PORTD2 (RS signal of LCD module),
PORTD5 (OCR1A as PWM controlled DC voltage generator).
Before using this function, you should install the LCD panel with screws first. Adjust the
contrast of the LCD panel via PORTD5. And you could adjust the contrast with
potentiometer R28 too.
#include <stdint.h>
#include <avr/io.h>
#include <util/twi.h>
#include <avr/delay.h>
#include <compat/deprecated.h>
#include <avr/interrupt.h>
#include <avr/hd44780.h>
#define uchar unsigned char
#define uint unsigned int
© 2004 -2008 Sure Electronics Inc.
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SAMPLE CODE
#define FREQ 4
#define TempRegAddr 0x00 // Address of Temperature sensor
#define ReadLM75Addr 0x91 // Device address is 0. Read
#define WriteLM75Addr 0x90 // Write
#define Twi_Stop() TWCR=_BV(TWINT)|_BV(TWSTO)|_BV(TWEN)
#define Twi_Start() TWCR=_BV(TWINT)|_BV(TWSTA)|_BV(TWEN)
#define check_TWINT() while(!(TWCR & (1<<TWINT))) // Wait for TWINT flag being set
#define Func_key (PINC&0x80)
#define Change_key (PINC&0x40)
// Function key
// Switch key
uint isr_cyc_cnt;
uint cvalue,fvalue;
// Memory Centigrade and Fahrenheit value
char cent_buf[6],fahr_buf[6];
// Centigrade and Fahrenheit value array
uchar reset_key_pressed,last_reset_key_pressed;
uchar Func_key_pressed,last_Func_key_pressed;
uchar change_key_pressed,last_change_key_pressed;
uchar LED_thousand,LED_hundred,LED_ten,LED_one;
uchar value_thousand,value_hundred,value_ten,value_one;
uchar temperature_flag;
uchar cnt_fuckey,cnt_chgkey;
uchar PWM_data;
char PWMbuf[6];
uchar key_flag=0;
char pointer=0;
uchar TempHigh;
uchar TempLow;
uchar TempSign,TempData;
uchar TwiStatus;
char LCD_name[]="Sure Electronics";
char LCD_Ver[]="Ver 1.0";
char Cent[]="Centigrade";
char Fahr[]="Fahrenheit";
char Cont[]="Contrast
";
char Current[]="Current Temperature"; //Current Temperature
DB-DP115_Ver1.0 _Page34
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
void InitPort(void);
void InitUsart(void);
void InitTwi(void);
void InitDevice(void);
void DelayMs(uint ms);
void PWM(uchar pwmduty);
char FuncKey(void);
char ChangeKey(void);
void TWITempRead(uchar ReadDeviceAddr,uchar WriteDeviceAddr,uchar RegAddr) ;
void LM75_Temperature(void);
void USART(uchar *sendbuf);
/*********** Initializtion ************************************* Beginning ***********************/
void InitPort(void)
{
ACSR &=0x7f;
DDRA=0xFF;
DDRB=0xFF;
DDRC=0x3C;
// Close Comparator
// All PortA is output port
// All PORTB is output port
// PC7 is for Switch SW1 Input
// PC6 is for Switch SW2 Input
//PC0,PC1 is for TWI
PORTC |=_BV(PORTC6)|_BV(PORTC7)|_BV(PORTC0)|_BV(PORTC1);
SFIOR&=~_BV(PUD);
DDRD=0xFE;
}
void InitUsart(void)
{
UCSRB=0x00;
UCSRA=0x00;
UBRRH=0x00;
UBRRL=0x0c;
// USART Baud Rate is 57600bps
UCSRC=(1<<URSEL)|(1<<USBS)|(3<<UCSZ0);
//Set frame format: 8data, 2stop
bit
UCSRB=_BV(RXEN)|_BV(TXEN);
//Enable reciver and transmitter
}
© 2004 -2008 Sure Electronics Inc.
DB-DP115_Ver1.0_Page35
AVRDEM 2 PLUS
SAMPLE CODE
void InitDevice(void)
{
cli();
InitPort();
InitUsart();
}
/*********** Initializtion ************************************* END *****************/
/*********** PWM ******************************* Beginning ******************************/
void DelayMs(uint ms)
{
uint i;
for(i=0;i<ms;i++)
_delay_loop_2(FREQ*250);
}
void PWM(uchar pwmduty)
{
TCCR2=_BV(WGM20)|_BV(COM21)|_BV(CS22); //CLK/64
TCNT2=0;
DDRD |= _BV(PD7);
OCR2=pwmduty;
DelayMs(100);
}
/*********** PWM ******************************* END ******************************/
/*********** Scan key status ******************************* Beginning *******************/
char FuncKey(void)
{
uchar temp;
if(Func_key==0x80)
Func_key_pressed=1;
else if(Func_key==0)
Func_key_pressed=0;
if((Func_key_pressed==0)&(last_Func_key_pressed==1))
{
DB-DP115_Ver1.0 _Page36
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
if(Func_key_pressed==0)cnt_fuckey++;
}
last_Func_key_pressed=Func_key_pressed;
temp=cnt_fuckey%3;
return temp;
}
char ChangeKey(void)
{
uchar temp;
if(Change_key==0x40)
change_key_pressed=1;
else if(Change_key==0)
change_key_pressed=0;
if((change_key_pressed==0)&(last_change_key_pressed==1))
{
if(change_key_pressed==0) cnt_chgkey++;
}
last_change_key_pressed=change_key_pressed;
temp=cnt_chgkey%11;
return temp;
}
/*********** Scan key status ******************************* END ******************************/
/*********** TWI operation routine ********************************** Beginning ***************/
void InitTwi(void)
{
TWCR= 0X00; //disable twi
TWBR= 0x12; //set bit rate
TWSR= 0x01; //set prescale
TWCR= 0x04; //enable twi
}
void TWITempRead(uchar ReadDeviceAddr,uchar WriteDeviceAddr,uchar RegAddr)
{
© 2004 -2008 Sure Electronics Inc.
DB-DP115_Ver1.0_Page37
AVRDEM 2 PLUS
SAMPLE CODE
while (TwiStatus != 0x08) // Check TWSR register. Clear the prescale bit.
{
Twi_Start();
// Send START signal
_delay_us(1);
TwiStatus=TWSR & 0xF8;
}
//StatusLihgting(0);
while (TwiStatus != 0x18)
// Check TWSR register. SLA+W signal has been
//sent, and ACK signal has been received.
{
TWDR = WriteDeviceAddr;
TWCR=0x84;
_delay_us(1);
TwiStatus=TWSR & 0xF8;
// Device Address (write)
}
while (TwiStatus != 0x28)
//DATA has been sent. ACK has been received
{
TWDR = RegAddr;
// Write LM75 address.
TWCR=0x84;
_delay_us(1);
TwiStatus=TWSR & 0xF8;
}
while (TwiStatus != 0x10)
//REPEATED START has been sent.
{
Twi_Start();
// Send REPEATED START
_delay_us(1);
TwiStatus=TWSR & 0xF8;
}
while (TwiStatus != 0x40)
// Check TWSR register. SLA+R has been sent.
//ACK has been received.
{
TWDR =ReadDeviceAddr;
TWCR=0x84;
_delay_us(1);
TwiStatus=TWSR & 0xF8;
// Device address
}
TwiStatus=0x00;
DB-DP115_Ver1.0 _Page38
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
while (TwiStatus != 0x50)
// DATA has been received. ACK has been sent.
{
TWCR=0xc4;
// Receive high 8-bit data. ACK has been sent.
_delay_us(1);
TempHigh=TWDR;
TwiStatus=TWSR & 0xF8;
}
while(TwiStatus != 0x58)
//DATA has been received. NACK has been sent.
{
TwiStatus=TWSR & 0xF8;
TWCR=0x84;
// Receive low 8-bit data. nACK has been sent.
_delay_us(1);
TempLow=TWDR;
}
Twi_Stop();
// Send STOP
}
/*********** TWI operation routine ********************************** END *********************/
/*********** LM75 Read routine ******************************** Beginning *******************/
//Read temperature value by LM75 temperature sensor
void LM75_Temperature(void)
{
uint temp_H,temp_L;
TWITempRead(ReadLM75Addr,WriteLM75Addr,TempRegAddr);
temp_H=TempHigh;
//High bits
temp_L=TempLow;
//Low bits
//Compute Centigrade
cvalue=(temp_H<<8)|temp_L;
cent_buf[0]=' ';
if((cvalue&0x80)==1)
{
cvalue=~cvalue+1;
cent_buf[0]='-';
}
cvalue=cvalue>>5;
cvalue=cvalue * 1.25;
cent_buf[1]=cvalue/100+48;
© 2004 -2008 Sure Electronics Inc.
//Calculate Base Complement
DB-DP115_Ver1.0_Page39
AVRDEM 2 PLUS
SAMPLE CODE
cent_buf[2]=(cvalue/10)%10+48;
cent_buf[3]='.';
cent_buf[4]=cvalue%10+48;
cent_buf[5]='\0';
//compute Fahrenheit
fvalue=((cvalue*9)/5)+32;
fahr_buf[0]=' ';
if((fvalue&0x80)==1)
{
fvalue=~fvalue+1;
fahr_buf[0]='-';
}
fahr_buf[1]=fvalue/100+48;
fahr_buf[2]=(fvalue/10)%10+48;
fahr_buf[3]='.';
fahr_buf[4]=fvalue%10+48;
fahr_buf[5]='\0';
//Calculate Base Complement
}
/*********** LM75 Read routine ************************************* END ***********************/
/*********** USART ************************************* Beginning ***********************/
void USART(uchar *sendbuf)
{
while((*sendbuf)!=0)
{
UDR = *(sendbuf++);
while(!(UCSRA & 0x40)) ;
UCSRA |= 0x40;
}
}
/*********** USART ************************************* END ***********************/
/************* LCD ************************************ Beginning *******************************/
/* DATA_PORT defines the port to which the LCD data lines are connected */
#define DATA_PORT
PORTB
#define DATA_PIN
PINB
#define TRIS_DATA_PORT DDRB
DB-DP115_Ver1.0 _Page40
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
/* CTRL_PORT defines the port where the control lines are connected.
* These are just samples, change to match your application.
*/
#define SET_RW_PIN sbi(PORTD,PD3) /* PORT for RW, RW=1 */
#define CLR_RW_PIN cbi(PORTD,PD3)
/* RW=0 */
#define SET_TRIS_RW sbi(DDRD,DDD3)
/* TRIS for RW */
#define CLR_TRIS_RW cbi(DDRD,DDD3)
/* TRIS for RW */
#define SET_RS_PIN sbi(PORTD,PD2) /* PORT for RS, RS=1 */
#define CLR_RS_PIN cbi(PORTD,PD2) /* PORT for RS, RS=0 */
#define SET_TRIS_RS sbi(DDRD,DDD2)
/* TRIS for RS */
#define CLR_TRIS_RS cbi(DDRD,DDD2)
/* TRIS for RS */
#define SET_E_PIN
sbi(PORTD,PD4) /* PORT for E ,1 */
#define CLR_E_PIN
cbi(PORTD,PD4) /* PORT for E ,0 */
#define SET_TRIS_E sbi(DDRD,DDD4)
/* TRIS for E */
#define CLR_TRIS_E cbi(DDRD,DDD4)
/* TRIS for E */
/* Display ON/OFF Control defines */
#define DON
0b00001111 /* Display on
*/
#define DOFF
0b00001011 /* Display off
*/
#define CURSOR_ON 0b00001111 /* Cursor on
*/
#define CURSOR_OFF 0b00001101 /* Cursor off
*/
#define BLINK_ON
0b00001111 /* Cursor Blink
*/
#define BLINK_OFF 0b00001110 /* Cursor No Blink */
/* Cursor or Display Shift defines */
#define SHIFT_CUR_LEFT
0b00010011
#define SHIFT_CUR_RIGHT 0b00010111
#define SHIFT_DISP_LEFT 0b00011011
#define SHIFT_DISP_RIGHT 0b00011111
/* Cursor shifts to the left */
/* Cursor shifts to the right */
/* Display shifts to the left */
/* Display shifts to the right */
/* Function Set defines */
#define EIGHT_BIT 0b00111111 /* 8-bit Interface
*/
#define LINES_5X7 0b00111011 /* 5x7 characters, multiple line */
#define PARAM_SCLASS auto
#define MEM_MODEL far /* Change this to near for small memory model */
/* OpenXLCD
© 2004 -2008 Sure Electronics Inc.
DB-DP115_Ver1.0_Page41
AVRDEM 2 PLUS
SAMPLE CODE
* Configures I/O pins for external LCD
*/
void OpenXLCD(unsigned char);
/* SetCGRamAddr
* Sets the character generator address
*/
void SetCGRamAddr(unsigned char);
/* SetDDRamAddr
* Sets the display data address
*/
void SetDDRamAddr(unsigned char);
/* BusyXLCD
* Returns the busy status of the LCD
*/
unsigned char BusyXLCD(void);
/* ReadAddrXLCD
* Reads the current address
*/
unsigned char ReadAddrXLCD(void);
/* ReadDataXLCD
* Reads a byte of data
*/
char ReadDataXLCD(void);
/* WriteCmdXLCD
* Writes a command to the LCD
*/
void WriteCmdXLCD(unsigned char);
/* WriteDataXLCD
* Writes a data byte to the LCD
*/
void WriteDataXLCD(char);
DB-DP115_Ver1.0 _Page42
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
/* putcXLCD
* A putc is a write
*/
#define putcXLCD WriteDataXLCD
/* putsXLCD
* Writes a string of characters to the LCD
*/
void putsXLCD(char *);
/* putrsXLCD
* Writes a string of characters in ROM to the LCD
*/
void putsXLCD(char *buffer);
/********************************************************************
*
Function Name: BusyXLCD
*
*
Return Value: char: busy status of LCD controller
*
*
Parameters:
void
*
*
Description:
This routine reads the busy status of the *
*
Hitachi HD44780 LCD controller.
*
********************************************************************/
unsigned char BusyXLCD(void)
{
SET_RW_PIN;
// Set the control bits for read BF
CLR_RS_PIN;
_delay_us(10);
SET_E_PIN;
// Clock in the command
_delay_us(10);
if(DATA_PIN&0x80)
// Read bit 7 (busy bit)
{
// If high
CLR_E_PIN;
// Reset clock line
CLR_RW_PIN;
// Reset control line
return 1;
// Return TRUE
}
else
// Bit 7 low
{
CLR_E_PIN;
// Reset clock line
CLR_RW_PIN;
// Reset control line
© 2004 -2008 Sure Electronics Inc.
DB-DP115_Ver1.0_Page43
AVRDEM 2 PLUS
SAMPLE CODE
return 0;
// Return FALSE
}
}
/********************************************************************
*
Function Name: OpenXLCD
*
Return Value: void
*
*
Parameters:
lcdtype: sets the type of LCD (lines)
*
*
Description:
This routine configures the LCD. Based on *
*
the Hitachi HD44780 LCD controller. The
*
*
routine will configure the I/O pins of the *
*
microcontroller, setup the LCD for 4- or
*
*
8-bit mode and clear the display. The user *
*
must provide three delay routines:
*
*
DelayFor18TCY() provides a 18 Tcy delay
*
*
DelayPORXLCD() provides at least 15ms delay *
*
DelayXLCD() provides at least 5ms delay
*
********************************************************************/
void OpenXLCD(unsigned char lcdtype)
{
// The data bits are made into inputs
*
DATA_PIN = 0;
TRIS_DATA_PORT = 0x00;
SET_TRIS_RW;
SET_TRIS_RS;
SET_TRIS_E;
CLR_RW_PIN;
CLR_RS_PIN;
CLR_E_PIN;
// All control signals made outputs
// R/W pin made low
// Register select pin made low
// Clock pin made low
// Delay for more than 15ms to allow for LCD Power on reset
_delay_ms(16);
// Setup interface to LCD
DATA_PORT = 0;
TRIS_DATA_PORT = 0xff;
DB-DP115_Ver1.0 _Page44
// Data port output
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
DATA_PORT = 0b00110000;
CLR_RW_PIN;
CLR_RS_PIN;
SET_E_PIN;
_delay_us(10);
CLR_E_PIN;
// Function set cmd(8-bit interface)
// R/W pin made low
// Register select pin made low
// Clock the cmd in
// Delay for at least 4.1ms
_delay_ms(6);
// Setup interface to LCD
DATA_PORT = 0;
DATA_PORT = 0b00110000;
CLR_RW_PIN;
CLR_RS_PIN;
SET_E_PIN;
_delay_us(10);
CLR_E_PIN;
// Function set cmd(8-bit interface)
// R/W pin made low
// Register select pin made low
// Clock the cmd in
// Delay for at least 100us
_delay_ms(1);
// Setup interface to LCD
DATA_PORT = 0;
DATA_PORT = 0b00110000;
SET_E_PIN;
_delay_us(10);
CLR_E_PIN;
TRIS_DATA_PORT = 0x00;
// Function set cmd(8-bit interface)
// Clock cmd in
// Make data port input
// Set data interface width, # lines, font
while(BusyXLCD());
// Wait if LCD busy
WriteCmdXLCD(lcdtype);
// Function set cmd
© 2004 -2008 Sure Electronics Inc.
DB-DP115_Ver1.0_Page45
AVRDEM 2 PLUS
SAMPLE CODE
// Turn the display on then off
while(BusyXLCD());
// Wait if LCD busy
WriteCmdXLCD(DOFF);
// Display OFF/Blink OFF
while(BusyXLCD());
// Wait if LCD busy
WriteCmdXLCD(DON);
// Display ON/Blink ON
while(BusyXLCD());
// Wait if LCD busy
WriteCmdXLCD(BLINK_OFF&CURSOR_OFF);
// Display ON/Blink
OFF
// Clear display
while(BusyXLCD());
WriteCmdXLCD(0x01);
// Wait if LCD busy
// Clear display
// Set entry mode inc, no shift
while(BusyXLCD());
// Wait if LCD busy
WriteCmdXLCD(SHIFT_CUR_LEFT); // Entry Mode
while(BusyXLCD());
WriteCmdXLCD(0b00000110);
// Set DD Ram address to 0
while(BusyXLCD());
SetDDRamAddr(0b00000111);
// Wait if LCD busy
// Set Display data ram address
to 0
return;
}
/********************************************************************
*
Function Name: putsXLCD
*
Return Value: void
*
Parameters:
buffer: pointer to string
*
Description:
This routine writes a string of bytes to the
*
Hitachi HD44780 LCD controller. The user
*
must check to see if the LCD controller is
*
busy before calling this routine. The data
*
is written to the character generator RAM or
*
the display data RAM depending on what the
DB-DP115_Ver1.0 _Page46
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
*
previous SetxxRamAddr routine was called.
********************************************************************/
void putsXLCD(char *buffer)
{
while(*buffer)
// Write data to LCD up to null
{
while(BusyXLCD()) ;
// Wait while LCD is busy
WriteDataXLCD(*buffer); // Write character to LCD
buffer++;
// Increment buffer
}
return;
}
/*********************************************************************
*
Function Name: ReadAddrXLCD
*
*
Return Value: char: address from LCD controller
*
*
Parameters:
void
*
*
Description:
This routine reads an address byte from the *
*
Hitachi HD44780 LCD controller. The user
*
*
must check to see if the LCD controller is *
*
busy before calling this routine. The address*
*
is read from the character generator RAM or *
*
the display data RAM depending on what the *
*
previous SetxxRamAddr routine was called.
*
*********************************************************************/
unsigned char ReadAddrXLCD(void)
{
char data;
// Holds the data retrieved from the LCD
SET_RW_PIN;
CLR_RS_PIN;
_delay_us(10);
SET_E_PIN;
_delay_us(10);
data = DATA_PIN;
© 2004 -2008 Sure Electronics Inc.
// Set control bits for the read
// Clock data out of the LCD controller
// Save the data in the register
DB-DP115_Ver1.0_Page47
AVRDEM 2 PLUS
SAMPLE CODE
CLR_E_PIN;
CLR_RW_PIN;
return (data&0x7f);
// Reset the control lines
// Return the address, Mask off the busy bit
}
/********************************************************************
*
Function Name: ReadDataXLCD
*
Return Value: char: data byte from LCD controller
*
*
Parameters:
void
*
*
Description:
This routine reads a data byte from the
*
*
Hitachi HD44780 LCD controller. The user
*
*
must check to see if the LCD controller is *
*
busy before calling this routine. The data *
*
is read from the character generator RAM or *
*
the display data RAM depending on what the *
*
previous SetxxRamAddr routine was called. *
********************************************************************/
char ReadDataXLCD(void)
{
char data;
SET_RS_PIN;
SET_RW_PIN;
_delay_us(10);
SET_E_PIN;
_delay_us(10);
data = DATA_PIN;
CLR_E_PIN;
CLR_RS_PIN;
CLR_RW_PIN;
CLR_E_PIN;
_delay_us(10);
SET_E_PIN;
_delay_us(10);
DB-DP115_Ver1.0 _Page48
*
// Set the control bits
// Clock the data out of the LCD
// Read the data
// Reset the control bits
// Reset the clock line
// Clock the next nibble out of the LCD
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
CLR_E_PIN;
CLR_RS_PIN;
CLR_RW_PIN;
return(data);
// Reset the control bits
// Return the data byte
}
/********************************************************************
*
Function Name: SetCGRamAddr
*
*
Return Value: void
*
*
Parameters:
CGaddr: character generator ram address
*
*
Description:
This routine sets the character generator *
*
address of the Hitachi HD44780 LCD
*
*
controller. The user must check to see if *
*
the LCD controller is busy before calling *
*
this routine.
*
********************************************************************/
void SetCGRamAddr(unsigned char CGaddr)
{
TRIS_DATA_PORT = 0xff;
// Make data port ouput
DATA_PORT = CGaddr | 0b01000000;
// Write cmd and address to port
CLR_RW_PIN;
// Set control signals
CLR_RS_PIN;
_delay_us(10);
SET_E_PIN;
// Clock cmd and address in
_delay_us(10);
CLR_E_PIN;
_delay_us(10);
TRIS_DATA_PORT = 0x00;
// Make data port inputs
return;
}
/********************************************************************
*
Function Name: SetDDRamAddr
*
Return Value: void
*
Parameters:
CGaddr: display data address
© 2004 -2008 Sure Electronics Inc.
*
*
*
DB-DP115_Ver1.0_Page49
AVRDEM 2 PLUS
SAMPLE CODE
*
Description:
This routine sets the display data address *
*
of the Hitachi HD44780 LCD controller. The *
*
user must check to see if the LCD controller*
*
is busy before calling this routine.
*
********************************************************************/
void SetDDRamAddr(unsigned char DDaddr)
{
TRIS_DATA_PORT = 0xff;
// Make port output
DATA_PORT = DDaddr | 0b10000000;
// Write cmd and address to port
CLR_RW_PIN;
// Set the control bits
CLR_RS_PIN;
_delay_us(10);
SET_E_PIN;
// Clock the cmd and address in
_delay_us(10);
CLR_E_PIN;
_delay_us(10);
TRIS_DATA_PORT = 0;
// Make port input
return;
}
/********************************************************************
*
Function Name: WriteCmdXLCD
*
*
Return Value: void
*
*
Parameters:
cmd: command to send to LCD
*
*
Description:
This routine writes a command to the Hitachi*
*
HD44780 LCD controller. The user must check *
*
to see if the LCD controller is busy before *
*
calling this routine.
*
********************************************************************/
void WriteCmdXLCD(unsigned char cmd)
{
TRIS_DATA_PORT = 0xff;
// Data port output
DATA_PORT = 0;
DATA_PORT |= cmd;
// Write command to data port
CLR_RW_PIN;
// Set the control signals
CLR_RS_PIN;
// for sending a command
_delay_us(10);
DB-DP115_Ver1.0 _Page50
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
SET_E_PIN;
_delay_us(10);
CLR_E_PIN;
_delay_us(10);
TRIS_DATA_PORT = 0x00;
// Clock the command in
// Data port input
return;
}
/********************************************************************
*
Function Name: WriteDataXLCD
*
*
Return Value: void
*
*
Parameters:
data: data byte to be written to LCD
*
*
Description:
This routine writes a data byte to the
*
*
Hitachi HD44780 LCD controller. The user
*
*
must check to see if the LCD controller is *
*
busy before calling this routine. The data *
*
is written to the character generator RAM or*
*
the display data RAM depending on what the *
*
previous SetxxRamAddr routine was called. *
********************************************************************/
void WriteDataXLCD(char data)
{
TRIS_DATA_PORT = 0xff;
// Make port output
DATA_PORT = data;
// Write data to port
SET_RS_PIN;
// Set control bits
CLR_RW_PIN;
_delay_us(10);
SET_E_PIN;
// Clock data into LCD
_delay_us(10);
CLR_E_PIN;
CLR_RS_PIN;
// Reset control bits
TRIS_DATA_PORT = 0x00;
// Make port input
return;
}
void InitLCD(void)
{
© 2004 -2008 Sure Electronics Inc.
DB-DP115_Ver1.0_Page51
AVRDEM 2 PLUS
SAMPLE CODE
OpenXLCD( EIGHT_BIT&LINES_5X7 );// configure external LCD
while(BusyXLCD()) ;
SetDDRamAddr(0x00);
putsXLCD(LCD_name);
// Wait if LCD busy
// Set Display data ram address to 0x00
// write to LCD
while(BusyXLCD()) ;
SetDDRamAddr(0x40);
putsXLCD(LCD_Ver);
_delay_ms(200);
// Wait if LCD busy
// Set Display data ram address to 0x40
// write to LCD
}
void LCD_Display(char *i)
{
// Set DD Ram address to 0
while(BusyXLCD()) ;
SetDDRamAddr(0x40);
// write to LCD
while(BusyXLCD()) ;
putsXLCD(i);
// Wait if LCD busy
// Set Display data ram address to 0
// Wait if LCD busy
}
/************** LCD ************************************** END *********************************/
/*************** Timer0 ISR ******************************* Beginning ****************************/
SIGNAL(SIG_OVERFLOW0)
{
unsigned int fkey_num,ckey_num;
TCNT0 = 0x70; //reload counter value
isr_cyc_cnt++;
LM75_Temperature();
//Read Temperature
if(key_flag==0)
{
fkey_num=FuncKey();
switch(fkey_num)
{
DB-DP115_Ver1.0 _Page52
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
case(0):
//Display "Centigrade"
{
LCD_Display(Cent);
putsXLCD(cent_buf);
PWM_data=fkey_num;
}break;
case(1):
//Display "Fahrenheit"
{
LCD_Display(Fahr);
putsXLCD(fahr_buf);
PWM_data=fkey_num;
}break;
case(2):
//Display Contrast
{
LCD_Display(Cont);
PWM_data=fkey_num;
}break;
}
if(Change_key==0)key_flag=1;
}
if(key_flag==1)
{
ckey_num=ChangeKey();
if((PWM_data==2)|(PWM_data==3))
{
switch(ckey_num)
{
case(0):
{
PWMbuf[0]='0';
PWMbuf[1]='%';
PWMbuf[2]=' ';
PWMbuf[3]=' ';
PWMbuf[4]=' ';
PWMbuf[5]=' ';
while(BusyXLCD());
SetDDRamAddr(0x4b);
putsXLCD(PWMbuf);
© 2004 -2008 Sure Electronics Inc.
//Display change
// Wait if LCD busy
// Set Display data ram address to 0x4b
DB-DP115_Ver1.0_Page53
AVRDEM 2 PLUS
SAMPLE CODE
}break;
case(1):
{
PWMbuf[0]='1';
PWMbuf[1]='0';
PWMbuf[2]='%';
PWMbuf[3]=' ';
PWMbuf[4]=' ';
PWMbuf[5]=' ';
while(BusyXLCD());
SetDDRamAddr(0x4b);
putsXLCD(PWMbuf);
}break;
case(2):
{
PWMbuf[0]='2';
PWMbuf[1]='0';
PWMbuf[2]='%';
PWMbuf[3]=' ';
PWMbuf[4]=' ';
PWMbuf[5]=' ';
while(BusyXLCD());
SetDDRamAddr(0x4b);
putsXLCD(PWMbuf);
}break;
case(3):
{
PWMbuf[0]='3';
PWMbuf[1]='0';
PWMbuf[2]='%';
PWMbuf[3]=' ';
PWMbuf[4]=' ';
PWMbuf[5]=' ';
while(BusyXLCD());
SetDDRamAddr(0x4b);
putsXLCD(PWMbuf);
}break;
case(4):
{
DB-DP115_Ver1.0 _Page54
// Wait if LCD busy
// Set Display data ram address to 0x4b
// Wait if LCD busy
// Set Display data ram address to 0x4b
// Wait if LCD busy
// Set Display data ram address to 0x4b
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
PWMbuf[0]='4';
PWMbuf[1]='0';
PWMbuf[2]='%';
PWMbuf[3]=' ';
while(BusyXLCD());
SetDDRamAddr(0x4b);
putsXLCD(PWMbuf);
}break;
case(5):
{
PWMbuf[0]='5';
PWMbuf[1]='0';
PWMbuf[2]='%';
PWMbuf[3]=' ';
PWMbuf[4]=' ';
PWMbuf[5]=' ';
while(BusyXLCD());
SetDDRamAddr(0x4b);
putsXLCD(PWMbuf);
}break;
case(6):
{
PWMbuf[0]='6';
PWMbuf[1]='0';
PWMbuf[2]='%';
PWMbuf[3]=' ';
PWMbuf[4]=' ';
PWMbuf[5]=' ';
while(BusyXLCD());
SetDDRamAddr(0x4b);
putsXLCD(PWMbuf);
}break;
case(7):
{
PWMbuf[0]='7';
PWMbuf[1]='0';
PWMbuf[2]='%';
PWMbuf[3]=' ';
PWMbuf[4]=' ';
© 2004 -2008 Sure Electronics Inc.
// Wait if LCD busy
// Set Display data ram address to 0x4b
// Wait if LCD busy
// Set Display data ram address to 0x4b
// Wait if LCD busy
// Set Display data ram address to 0x4b
DB-DP115_Ver1.0_Page55
AVRDEM 2 PLUS
SAMPLE CODE
PWMbuf[5]=' ';
while(BusyXLCD());
SetDDRamAddr(0x4b);
putsXLCD(PWMbuf);
}break;
case(8):
{
PWMbuf[0]='8';
PWMbuf[1]='0';
PWMbuf[2]='%';
PWMbuf[3]=' ';
PWMbuf[4]=' ';
PWMbuf[5]=' ';
while(BusyXLCD());
SetDDRamAddr(0x4b);
putsXLCD(PWMbuf);
}break;
case(9):
{
PWMbuf[0]='9';
PWMbuf[1]='0';
PWMbuf[2]='%';
PWMbuf[3]=' ';
PWMbuf[4]=' ';
PWMbuf[5]=' ';
while(BusyXLCD());
SetDDRamAddr(0x4b);
putsXLCD(PWMbuf);
}break;
case(10):
{
PWMbuf[0]='1';
PWMbuf[1]='0';
PWMbuf[2]='0';
PWMbuf[3]='%';
PWMbuf[4]=' ';
PWMbuf[5]=' ';
while(BusyXLCD());
SetDDRamAddr(0x4b);
DB-DP115_Ver1.0 _Page56
// Wait if LCD busy
// Set Display data ram address to 0x4b
// Wait if LCD busy
// Set Display data ram address to 0x4b
// Wait if LCD busy
// Set Display data ram address to 0x4b
// Wait if LCD busy
// Set Display data ram address to 0x4b
© 2004 -2008 Sure Electronics Inc.
AVRDEM 2 PLUS
SAMPLE CODE
putsXLCD(PWMbuf);
}break;
}
}
if(Func_key==0)key_flag=0;
}
if(isr_cyc_cnt%512==0)
{
PWM(4);
USART(Current);
UDR=13;
UDR=10;
PWM(0);
_delay_ms(25);
USART(cent_buf);
_delay_ms(1);
USART(Cent);
UDR=13;
UDR=10;
_delay_ms(25);
USART(fahr_buf);
_delay_ms(1);
USART(Fahr);
UDR=13;
UDR=10;
_delay_ms(25);
}
}
/*************** Timer0 ISR ******************************* END ****************************/
int main (void)
{
InitDevice();
InitTwi();
InitLCD();
TCNT0=0;
© 2004 -2008 Sure Electronics Inc.
DB-DP115_Ver1.0_Page57
AVRDEM 2 PLUS
SAMPLE CODE
TCCR0=4; //prescale: ck/1024
TIMSK=_BV(TOIE0);
sei();
while(1) ;
}
DB-DP115_Ver1.0 _Page58
© 2004 -2008 Sure Electronics Inc.