Files
arduino-c/at28c256/at28c256.c
2022-07-29 19:47:32 +02:00

64 lines
1.7 KiB
C

#include <util/delay.h>
#include "at28c256.h"
#include "../ard/pins.h"
unsigned char _ck, _addr, _oe, _we, _io0, _io1, _io2, _io3, _io4, _io5, _io6, _io7;
void at28c256_init(unsigned char ck, unsigned char addr, unsigned char oe, unsigned char we, unsigned char io0, unsigned char io1, unsigned char io2, unsigned char io3, unsigned char io4, unsigned char io5, unsigned char io6, unsigned char io7) {
pin_mode(ck, OUTPUT);
digital_write(ck, LOW); // disable
pin_mode(addr, OUTPUT);
digital_write(addr, LOW); // disable
pin_mode(oe, OUTPUT);
digital_write(oe, HIGH); // disable
pin_mode(we, OUTPUT);
digital_write(we, HIGH); // disable
_ck = ck;
_addr = addr;
_oe = oe;
_we = we;
_io0 = io0;
_io1 = io1;
_io2 = io2;
_io3 = io3;
_io4 = io4;
_io5 = io5;
_io6 = io6;
_io7 = io7;
}
void at28c256_write(unsigned short addr, unsigned char data) {
// just to be safe, disable output
digital_write(_oe, HIGH);
// set the address
unsigned int i;
for(i = 0; i < 16; i++) {
if(addr & (1 << (15-i))) {
digital_write(_addr, HIGH);
} else {
digital_write(_addr, LOW);
}
digital_write(_ck, HIGH);
digital_write(_ck, LOW);
}
digital_write(_addr, LOW);
// write data
digital_write(_io0, data & 1);
digital_write(_io1, data & 1<<1);
digital_write(_io2, data & 1<<2);
digital_write(_io3, data & 1<<3);
digital_write(_io4, data & 1<<4);
digital_write(_io5, data & 1<<5);
digital_write(_io6, data & 1<<6);
digital_write(_io7, data & 1<<7);
digital_write(_we, data);
_delay_us(1); // min 100ns
digital_write(_we, HIGH);
}