How to configure ATmega8 portc port?

[chaitana]

I'm using atmega8 with lcd nokia 3310.
When I use spi pin and some of portb as a control reset, ce and d/c. It's ok.
But I changed control to portc (only control not spi). Lcd not active.
I test lcd pin ce. It can't switch to hi. I'm check data sheet portc is adc port.
How to config port?
May I miss some hardware pin connect to vcc or ground?

 

[ctownsend]

can+spi+portc

I'm using atmega8 with lcd nokia 3310.
When I use spi pin and some of portb as a control reset, ce and d/c. It's ok.
But I changed control to portc (only control not spi). Lcd not active.
I test lcd pin ce. It can't switch to hi. I'm check data sheet portc is adc port.
How to config port?
May I miss some hardware pin connect to vcc or ground?

you must configure that pin as an output. The data direction register
must be 1 for output, 0 for input on the right pin.

so if you are using PC1 as an output, the instruction will look like this:

ldi	r16,0b00000010      ;PC1 = output, others are inputs
out    DDRC,r16

Good Luck

 

[chaitana]

avr portc

Dear ctownsend
The port is set to output. I'm only change define control port from portb to portc.
It's work in portb.

// Lcd Port Settings
#define LCD_SER_PORT PORTB
#define LCD_SER_DDR DDRB
#define LCD_SCLK_PIN PINB5
#define LCD_MOSI_PIN PINB3

// Lcd Port control
#define LCD_CTRL_PORT PORTC
#define LCD_CTRL_DDR DDRC
#define LCD_DC_PIN PINC1
#define LCD_CE_PIN PINC2
#define LCD_RTS_PIN PINC4

// Set output bits on port ctrl.
LCD_CTRL_DDR |= (1 << LCD_DC_PIN ) | (1 << LCD_CE_PIN ) | (1 << LCD_RTS_PIN );
LCD_CTRL_PORT|= (1 << LCD_DC_PIN ) | (1 << LCD_CE_PIN ) | (1 << LCD_RTS_PIN );

 

[nandhu015]

Re: need help avr portc

Hi

Check PORTC 6

If you had enabled external reset then there will be prob.

the mcu will reset whenever you change the status of PC6

Regards
Nandhu