AVR Freaks

The LCD display is working.

There is indeed a difference in the Batron LCD display used in Avr Applnote AVR155, and the batron that i used.

AVR155 uses Batron BT21605V-SRE-I2C-COG
I Use BATRON BTHQ 21605AV-YETF-LED04-I2C-5V

The ..COG type means Chip-On-Glas. While
mine is an LCD mounted on a PCB.

The contrast LCD reset and the Contrast steering signals are brought outside on the COG type. On the PCB version these features have to be set via I2C commands.

So the fact that my LCD screen stayed BLANK was due to a contrast problem.

After initialising the constrast Values the LCD worked.

You can find a list of initialisation command on the website DATA-MODULE AG

www.data-module.de Click further on
- Support
- Driver
- PCF2119 BT21605

Here they are anyhow.

//Initialisation sample and Ram writing routine for PCF2119

void Display_init(void)
{
Reset=1;
delay_ms(5);
Reset=0;
delay_ms(5000);
iic_start();
iic_write(0x76); // i2c slave Address
iic_write(0x00); // Control byte for Instruction
iic_write(0x34); // DL: 8 bits, M: 16 by two line display, SL: 1:18, H: normal instruction set
iic_write(0x0C); // D: Display on, C: curser off, B: blink off
iic_write(0x06); // I/D: increment, S: no shift
iic_write(0x35); // DL: 8 bits, M: 16 by two line, SL: 1:18, H: extended instruction set
iic_write(0x04); // P: left to right, Q: top to bottom
iic_write(0x10); // TC1: 0, TC2: 0
iic_write(0x42); // HV Stages 3
iic_write(0x9f); // set Vlcd, store to VA
iic_write(0x34); // DL: 8 bits, M: two line, SL: 1:18, H: normal instruction set
iic_write(0x80); // DDRAM Address set to 00hex
iic_write(0x02); // return home
iic_stop();
}

void Write_text(void)
{
int i;
iic_start();
iic_write(0x76); // i2c slave Address
iic_write(0x00); // Control byte for Instruction
iic_write(0x80); // DDRAM Address set to 00hex
iic_stop();

iic_start();
iic_write(0x76); // i2c slave Adress
iic_write(0x40); // Control byte for Data
for (i=1;i<=16;i++)
{
iic_write(0xC0+i); // Write ABCDE....
}
iic_stop();
iic_start();
iic_write(0x76); // i2c slave Adress
iic_write(0x00); // Control byte for Instruction
iic_write(0xc0); // DDRAM Address set to 10hex
iic_stop();

iic_start();
iic_write(0x76); // i2c slave Address
iic_write(0x40); // Control byte for Data
for (i=1;i<=16;i++)
{
iic_write(0xe0+i); // Write abcde....
}
iic_stop();
}

void upside_down(void)
{
iic_start();
iic_write(0x76);
iic_write(0x00); // Control byte for Instruction
iic_write(0x35); // DL: 8 bits, M: 16 by two line, SL: 1:18, H: extended instruction set
iic_write(0x07); // P=1; Q=1;
iic_stop();
}

void normal(void)
{
iic_start();
iic_write(0x76);
iic_write(0x00); // Control byte for Instruction
iic_write(0x35); // DL: 8 bits, M: 16 by two line, SL: 1:18, H: extended instruction set
iic_write(0x04); // P=0; Q=0;
iic_stop();
}

Thanks for all reply's
Fabrizio