I've been having trouble programming my EEPROM's for a while now and finally bit the bullet and bought a cheap logic analyser from Aliexpress, which works great! Upon testing Ben's Arduino EEPROM programmer that I built I noticed that the EEPROM is recieving pulses to the data pins but no pulses to the address pins. I've traced this back to the Arduino and have noticed that pin D3 - SHIFT_CLK is pulsing but D2 - SHIFT_DATA is not and is just holding high . The Arduino code is taken directly from Ben's github. it looks correct and i've tried reflashing at multiple times. WRITE_ENABLE, SHIFT LATCH and the EEPROM DIgital write pins all seem to be working fine. It's just not producing a serial output for the adresses. This seems like an IDE issue, I'm hoping someone might be able to help
I've tried this with a nano every and a funduino uno. same result. (baud: 57600)
Logic Analyser results from pulseview
My wiring
/**
* This sketch is specifically for programming the EEPROM used in the 8-bit
* decimal display decoder described in https://youtu.be/dLh1n2dErzE
*/
#define SHIFT_DATA 2
#define SHIFT_CLK 3
#define SHIFT_LATCH 4
#define EEPROM_D0 5
#define EEPROM_D7 12
#define WRITE_EN 13
/*
Output the address bits and outputEnable signal using shift registers.
*/
void setAddress(int address, bool outputEnable) {
shiftOut(SHIFT_DATA, SHIFT_CLK, MSBFIRST, (address >> 8) | (outputEnable ? 0x00 : 0x80));
shiftOut(SHIFT_DATA, SHIFT_CLK, MSBFIRST, address);
digitalWrite(SHIFT_LATCH, LOW);
digitalWrite(SHIFT_LATCH, HIGH);
digitalWrite(SHIFT_LATCH, LOW);
}
/*
Read a byte from the EEPROM at the specified address.
*/
byte readEEPROM(int address) {
for (int pin = EEPROM_D0; pin <= EEPROM_D7; pin += 1) {
pinMode(pin, INPUT);
}
setAddress(address, /*outputEnable*/ true);
byte data = 0;
for (int pin = EEPROM_D7; pin >= EEPROM_D0; pin -= 1) {
data = (data << 1) + digitalRead(pin);
}
return data;
}
/*
Write a byte to the EEPROM at the specified address.
*/
void writeEEPROM(int address, byte data) {
setAddress(address, /*outputEnable*/ false);
for (int pin = EEPROM_D0; pin <= EEPROM_D7; pin += 1) {
pinMode(pin, OUTPUT);
}
for (int pin = EEPROM_D0; pin <= EEPROM_D7; pin += 1) {
digitalWrite(pin, data & 1);
data = data >> 1;
}
digitalWrite(WRITE_EN, LOW);
delayMicroseconds(1);
digitalWrite(WRITE_EN, HIGH);
delay(10);
}
/*
Read the contents of the EEPROM and print them to the serial monitor.
*/
void printContents() {
for (int base = 0; base <= 255; base += 16) {
byte data[16];
for (int offset = 0; offset <= 15; offset += 1) {
data[offset] = readEEPROM(base + offset);
}
char buf[80];
sprintf(buf, "%03x: %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x",
base, data[0], data[1], data[2], data[3], data[4], data[5], data[6], data[7],
data[8], data[9], data[10], data[11], data[12], data[13], data[14], data[15]);
Serial.println(buf);
}
}
void setup() {
// put your setup code here, to run once:
pinMode(SHIFT_DATA, OUTPUT);
pinMode(SHIFT_CLK, OUTPUT);
pinMode(SHIFT_LATCH, OUTPUT);
digitalWrite(WRITE_EN, HIGH);
pinMode(WRITE_EN, OUTPUT);
Serial.begin(57600);
// Bit patterns for the digits 0..9
byte digits[] = { 0x7e, 0x30, 0x6d, 0x79, 0x33, 0x5b, 0x5f, 0x70, 0x7f, 0x7b };
Serial.println("Programming ones place");
for (int value = 0; value <= 255; value += 1) {
writeEEPROM(value, digits[value % 10]);
}
Serial.println("Programming tens place");
for (int value = 0; value <= 255; value += 1) {
writeEEPROM(value + 256, digits[(value / 10) % 10]);
}
Serial.println("Programming hundreds place");
for (int value = 0; value <= 255; value += 1) {
writeEEPROM(value + 512, digits[(value / 100) % 10]);
}
Serial.println("Programming sign");
for (int value = 0; value <= 255; value += 1) {
writeEEPROM(value + 768, 0);
}
Serial.println("Programming ones place (twos complement)");
for (int value = -128; value <= 127; value += 1) {
writeEEPROM((byte)value + 1024, digits[abs(value) % 10]);
}
Serial.println("Programming tens place (twos complement)");
for (int value = -128; value <= 127; value += 1) {
writeEEPROM((byte)value + 1280, digits[abs(value / 10) % 10]);
}
Serial.println("Programming hundreds place (twos complement)");
for (int value = -128; value <= 127; value += 1) {
writeEEPROM((byte)value + 1536, digits[abs(value / 100) % 10]);
}
Serial.println("Programming sign (twos complement)");
for (int value = -128; value <= 127; value += 1) {
if (value < 0) {
writeEEPROM((byte)value + 1792, 0x01);
} else {
writeEEPROM((byte)value + 1792, 0);
}
}
// Read and print out the contents of the EERPROM
Serial.println("Reading EEPROM");
printContents();
}
void loop() {
// put your main code here, to run repeatedly:
}
Ben's code uploaded directly from his github
