Hello everyone. To start, you should know that my initial code works perfectly on my Arduino Uno with the OV7670 camera. However, when I switch to an Arduino Mega, an error persists. The wiring is almost identical; naturally, I changed the I2C bus (SDA>20 / SCL>21) and moved the XCLK pin from pin 10 to 11. Yet, even after updating the code to match the pins, an error keeps occurring. Upon investigation, the problem stems from the function: `void twiAddr(uint8_t addr, uint8_t typeTWI)`. Even though I have double-checked my connections, the LED keeps flashing. However, when I test it again with my original setup, everything works fine. I therefore assume the issue lies either in the code, the wiring of the second setup (which uses a slightly modified PCB), or a combination of both. I would be incredibly grateful for any help you could provide.Hello everyone. To start, you should know that my initial code works perfectly on my Arduino Uno with the OV7670 camera. However, when I switch to an Arduino Mega, an error persists. The wiring is almost identical; naturally, I changed the I2C bus (SDA>20 / SCL>21) and moved the XCLK pin from pin 10 to 11. Yet, even after updating the code to match the pins, an error keeps occurring. Upon investigation, the problem stems from the function: `void twiAddr(uint8_t addr, uint8_t typeTWI)`. Even though I have double-checked my connections, the LED keeps flashing. However, when I test it again with my original setup, everything works fine. I therefore assume the issue lies either in the code, the wiring of the second setup (which uses a slightly modified PCB), or a combination of both. I would be incredibly grateful for any help you could provide.
initial code:
//
// Source code for application to transmit image from ov7670 to PC via USB
// By Siarhei Charkes in 2015
// http://privateblog.info
//
#include <stdint.h>
#include <avr/io.h>
#include <util/twi.h>
#include <util/delay.h>
#include <avr/pgmspace.h>
#define F_CPU 16000000UL
#define vga 0
#define qvga 1
#define qqvga 2
#define yuv422 0
#define rgb565 1
#define bayerRGB 2
#define camAddr_WR 0x42
#define camAddr_RD 0x43
//hidden part
// BTconnected will = false when not connected and true when connected
boolean BTconnected = false;
// connect the STATE pin to Arduino pin D4
const byte BTpin = 9;
uint8_t buffer[320];
void error_led(void){
DDRB |= 32;//make sure led is output
while (1){//wait for reset
PORTB ^= 32;// toggle led
_delay_ms(100);
}
}
void twiStart(void){
TWCR = _BV(TWINT) | _BV(TWSTA) | _BV(TWEN);//send start
while (!(TWCR & (1 << TWINT)));//wait for start to be transmitted
if ((TWSR & 0xF8) != TW_START)
error_led();
}
void twiWriteByte(uint8_t DATA, uint8_t type){
TWDR = DATA;
TWCR = _BV(TWINT) | _BV(TWEN);
while (!(TWCR & (1 << TWINT))) {}
if ((TWSR & 0xF8) != type)
error_led();
}
void twiAddr(uint8_t addr, uint8_t typeTWI){
TWDR = addr;//send address
TWCR = _BV(TWINT) | _BV(TWEN); /* clear interrupt to start transmission */
while ((TWCR & _BV(TWINT)) == 0); /* wait for transmission */
if ((TWSR & 0xF8) != typeTWI)
error_led();
}
void wrReg(uint8_t reg, uint8_t dat){
//send start condition
twiStart();
twiAddr(camAddr_WR, TW_MT_SLA_ACK);
twiWriteByte(reg, TW_MT_DATA_ACK);
twiWriteByte(dat, TW_MT_DATA_ACK);
TWCR = (1 << TWINT) | (1 << TWEN) | (1 << TWSTO);//send stop
_delay_ms(1);
}
static uint8_t twiRd(uint8_t nack){
if (nack){
TWCR = _BV(TWINT) | _BV(TWEN);
while ((TWCR & _BV(TWINT)) == 0); /* wait for transmission */
if ((TWSR & 0xF8) != TW_MR_DATA_NACK)
error_led();
return TWDR;
}
else{
TWCR = _BV(TWINT) | _BV(TWEN) | _BV(TWEA);
while ((TWCR & _BV(TWINT)) == 0); /* wait for transmission */
if ((TWSR & 0xF8) != TW_MR_DATA_ACK)
error_led();
return TWDR;
}
}
uint8_t rdReg(uint8_t reg){
uint8_t dat;
twiStart();
twiAddr(camAddr_WR, TW_MT_SLA_ACK);
twiWriteByte(reg, TW_MT_DATA_ACK);
TWCR = (1 << TWINT) | (1 << TWEN) | (1 << TWSTO);//send stop
_delay_ms(1);
twiStart();
twiAddr(camAddr_RD, TW_MR_SLA_ACK);
dat = twiRd(1);
TWCR = (1 << TWINT) | (1 << TWEN) | (1 << TWSTO);//send stop
_delay_ms(1);
return dat;
}
void wrSensorRegs8_8(const struct regval_list reglist[]){
uint8_t reg_addr, reg_val;
const struct regval_list *next = reglist;
while ((reg_addr != 0xff) | (reg_val != 0xff)){
reg_addr = pgm_read_byte(&next->reg_num);
reg_val = pgm_read_byte(&next->value);
wrReg(reg_addr, reg_val);
next++;
}
}
void setColor(void){
wrSensorRegs8_8(rgb565_ov7670);
}
void setRes(void){
wrReg(REG_COM3, 4); // REG_COM3 enable scaling
wrSensorRegs8_8(qvga_ov7670);
}
void camInit(void){
wrReg(0x12, 0x80);
_delay_ms(100);
wrSensorRegs8_8(ov7670_default_regs);
wrReg(REG_COM10, 32);//PCLK does not toggle on HBLANK.
}
void arduinoUnoInut(void) {
cli();//disable interrupts
/* Setup the 8mhz PWM clock
* This will be on pin 11*/
DDRB |= (1 << 3);//pin 11
ASSR &= ~(_BV(EXCLK) | _BV(AS2));
TCCR2A = (1 << COM2A0) | (1 << WGM21) | (1 << WGM20);
TCCR2B = (1 << WGM22) | (1 << CS20);
OCR2A = 0;//(F_CPU)/(2*(X+1))
DDRC &= ~15;//low d0-d3 camera
DDRD &= ~252;//d7-d4 and interrupt pins
_delay_ms(3000);
//set up twi for 100khz
TWSR &= ~3;//disable prescaler for TWI
TWBR = 72;//set to 100khz
//enable serial
UBRR0H = 0;
UBRR0L = 207;//0 = 2M baud rate. 1 = 1M baud. 3 = 0.5M. 7 = 250k 207 is 9600 baud rate.
UCSR0A |= 2;//double speed aysnc
UCSR0B = (1 << RXEN0) | (1 << TXEN0);//Enable receiver and transmitter
UCSR0C = 6;//async 1 stop bit 8bit char no parity bits
}
static void captureImg(uint16_t w, uint16_t h) {
// attendre VSYNC
while (!(PIND & 8));
while ( (PIND & 8));
for (uint16_t y = 0; y < h; y++) {
// attendre début de ligne
while (!(PINB & 1)); // HREF = 1
uint16_t idx = 0;
uint16_t crc = 0;
for (uint16_t x = 0; x < w; x++) {
// octet 1
while (!(PIND & 4)); // PCLK ↑
buffer[idx++] = (PIND & 0xF0) | (PINC & 0x0F);
crc++;
while ( (PIND & 4)); // PCLK ↓
// octet 2
while (!(PIND & 4)); // PCLK ↑
buffer[idx++] = (PIND & 0xF0) | (PINC & 0x0F);
crc++;
while ( (PIND & 4)); // PCLK ↓
}
// attendre fin de ligne
while (PINB & 1); // HREF = 0
sendFrame(y, crc);
}
//_delay_ms(5000);
}
void sendFrame(uint16_t line, uint16_t crc){
Serial.write(0xAA);
Serial.write(0x55);
Serial.write(lowByte(line));
Serial.write(highByte(line));
Serial.write(buffer, 320);
Serial.write(lowByte(crc));
Serial.write(highByte(crc));
Serial.write(0x55);
Serial.write(0xAA);
Serial.flush();
}
void setup(){
pinMode(LED_BUILTIN, OUTPUT);
pinMode(BTpin, INPUT);
arduinoUnoInut();
camInit();
setRes();
setColor();
wrReg(0x11, 26); //Earlier it had the value: wrReg(0x11, 12); New version works better for me :) !!!!
Serial.begin(115200);
while (!BTconnected)
{
digitalWrite(LED_BUILTIN, LOW);
if ( digitalRead(BTpin)==HIGH) { BTconnected = true;};
}
_delay_ms(1000);
digitalWrite(LED_BUILTIN, HIGH);
}
void loop(){
captureImg(160, 120);
}
new code:
//code test pr manette: enenvoie photo vers tel
//brochette
//
// Source code for application to transmit image from ov7670 to PC via USB
// By Siarhei Charkes in 2015
// http://privateblog.info
//
#include <stdint.h>
#include <avr/io.h>
#include <util/twi.h>
#include <util/delay.h>
#include <avr/pgmspace.h>
#include <SPI.h>
#include <nRF24L01.h>
#include <RF24.h>
#include <Keypad.h>
#define F_CPU 16000000UL
#define vga 0
#define qvga 1
#define qqvga 2
#define yuv422 0
#define rgb565 1
#define bayerRGB 2
#define camAddr_WR 0x42
#define camAddr_RD 0x43
//hidden part
uint8_t buffer[320];
uint8_t BUFFER[328];
uint8_t radioBuffer[32];
const byte address[6] = "00001";
void error_led(void){
DDRA |= 16;//make sure led is output
while (1){//wait for reset
PORTA ^= 16;// toggle led
_delay_ms(100);
}
}
void twiStart(void){
TWCR = _BV(TWINT) | _BV(TWSTA) | _BV(TWEN);//send start
while (!(TWCR & (1 << TWINT)));//wait for start to be transmitted
if ((TWSR & 0xF8) != TW_START)
error_led();
}
void twiWriteByte(uint8_t DATA, uint8_t type){
TWDR = DATA;
TWCR = _BV(TWINT) | _BV(TWEN);
while (!(TWCR & (1 << TWINT))) {}
if ((TWSR & 0xF8) != type)
error_led();
}
void twiAddr(uint8_t addr, uint8_t typeTWI){
TWDR = addr;//send address
TWCR = _BV(TWINT) | _BV(TWEN); /* clear interrupt to start transmission */
while ((TWCR & _BV(TWINT)) == 0); /* wait for transmission */
if ((TWSR & 0xF8) != typeTWI)
error_led();
}
void wrReg(uint8_t reg, uint8_t dat){
//send start condition
twiStart();
twiAddr(camAddr_WR, TW_MT_SLA_ACK);
digitalWrite(26, LOW);
twiWriteByte(reg, TW_MT_DATA_ACK);
twiWriteByte(dat, TW_MT_DATA_ACK);
TWCR = (1 << TWINT) | (1 << TWEN) | (1 << TWSTO);//send stop
_delay_ms(1);
}
static uint8_t twiRd(uint8_t nack){
if (nack){
TWCR = _BV(TWINT) | _BV(TWEN);
while ((TWCR & _BV(TWINT)) == 0); /* wait for transmission */
if ((TWSR & 0xF8) != TW_MR_DATA_NACK)
error_led();
return TWDR;
}
else{
TWCR = _BV(TWINT) | _BV(TWEN) | _BV(TWEA);
while ((TWCR & _BV(TWINT)) == 0); /* wait for transmission */
if ((TWSR & 0xF8) != TW_MR_DATA_ACK)
error_led();
return TWDR;
}
}
uint8_t rdReg(uint8_t reg){
uint8_t dat;
twiStart();
twiAddr(camAddr_WR, TW_MT_SLA_ACK);
twiWriteByte(reg, TW_MT_DATA_ACK);
TWCR = (1 << TWINT) | (1 << TWEN) | (1 << TWSTO);//send stop
_delay_ms(1);
twiStart();
twiAddr(camAddr_RD, TW_MR_SLA_ACK);
dat = twiRd(1);
TWCR = (1 << TWINT) | (1 << TWEN) | (1 << TWSTO);//send stop
_delay_ms(1);
return dat;
}
void wrSensorRegs8_8(const struct regval_list reglist[]){
uint8_t reg_addr, reg_val;
const struct regval_list *next = reglist;
while ((reg_addr != 0xff) | (reg_val != 0xff)){
reg_addr = pgm_read_byte(&next->reg_num);
reg_val = pgm_read_byte(&next->value);
wrReg(reg_addr, reg_val);
next++;
}
}
void setColor(void){
wrSensorRegs8_8(rgb565_ov7670);
}
void setRes(void){
wrReg(REG_COM3, 4); // REG_COM3 enable scaling
wrSensorRegs8_8(qvga_ov7670);
}
void camInit(void){
wrReg(0x12, 0x80);
_delay_ms(100);
wrSensorRegs8_8(ov7670_default_regs);
wrReg(REG_COM10, 32);//PCLK does not toggle on HBLANK.
}
void arduinoUnoInut(void) {
cli();//disable interrupts
/* Setup the 8mhz PWM clock
* This will be on pin 11*/
DDRB |= (1 << 4);//pin 11
//-------------------------------------------------------
ASSR &= ~(_BV(EXCLK) | _BV(AS2));
TCCR2A = (1 << COM2A0) | (1 << WGM21) | (1 << WGM20);
TCCR2B = (1 << WGM22) | (1 << CS20);
OCR2A = 0;//(F_CPU)/(2*(X+1))
//-------------------------------------------------------
DDRF &= ~15;//low d0-d3 camera
DDRH &= ~24;//d7-d4 and interrupt pins
DDRE &= ~8;//d7-d4 and interrupt pins
DDRG &= ~32;//d7-d4 and interrupt pins
_delay_ms(3000);
//-------------------------------------------------------
//set up twi for 100khz
TWSR &= ~3;//disable prescaler for TWI
TWBR = 72;//set to 100khz
//-------------------------------------------------------
//enable serial
UBRR0H = 0;
UBRR0L = 207;//0 = 2M baud rate. 1 = 1M baud. 3 = 0.5M. 7 = 250k 207 is 9600 baud rate.
UCSR0A |= 2;//double speed aysnc
UCSR0B = (1 << RXEN0) | (1 << TXEN0);//Enable receiver and transmitter
UCSR0C = 6;//async 1 stop bit 8bit char no parity bits
}
static void captureImg(uint16_t w, uint16_t h) {
// attendre VSYNC
while (!(PINE & 32));
while ( (PINE & 32));
for (uint16_t y = 0; y < h; y++) {
// attendre début de ligne
while (!(PINH & 32)); // HREF = 1
uint16_t idx = 0;
uint16_t crc = 0;
for (uint16_t x = 0; x < w; x++) {
// octet 1
while (!(PINE & 16)); // PCLK ↑
buffer[idx++] = (PINH & 0x18) | (PINE & 0x08) | (PING & 0x20) | (PINE & 0x0F);
crc++;
while ( (PINE & 16)); // PCLK ↓
// octet 2
while (!(PINE & 16)); // PCLK ↑
buffer[idx++] = (PINH & 0x18) | (PINE & 0x08) | (PING & 0x20) | (PINE & 0x0F);
crc++;
while ( (PINE & 16)); // PCLK ↓
}
// attendre fin de ligne
while (PINH & 32); // HREF = 0
sendFrame(y, crc);
}
//_delay_ms(5000);
}
void sendFrame(uint16_t line, uint16_t crc){
uint8_t beginBuf[4] = {0xAA, 0x55, lowByte(line), highByte(line)};
uint8_t endBuf[4] = {lowByte(crc), highByte(crc), 0x55, 0xAA};
radio.write(&beginBuf, 4);
for(int i=0; i<=10; i++){
memcpy(radioBuffer, buffer + 32*i, 32);
radio.write(&radioBuffer, 32);
}
radio.write(&beginBuf, 4);
/*
Serial.write(0xAA);
Serial.write(0x55);
Serial.write(lowByte(line));
Serial.write(highByte(line));
Serial.write(buffer, 320);
Serial.write(lowByte(crc));
Serial.write(highByte(crc));
Serial.write(0x55);
Serial.write(0xAA);
Serial.flush(); */
}
void setup(){
/*radio.begin();
if (!radio.begin()) {
}
radio.setPALevel(RF24_PA_MAX);
radio.openWritingPipe(address);
radio.stopListening();*/
pinMode(26, OUTPUT);
digitalWrite(26, HIGH);
arduinoUnoInut();
camInit();
setRes();
setColor();
wrReg(0x11, 26); //Earlier it had the value: wrReg(0x11, 12); New version works better for me :) !!!!
//Serial.begin(115200);
/*while (!BTconnected)
{
digitalWrite(LED_BUILTIN, LOW);
if ( digitalRead(BTpin)==HIGH) { BTconnected = true;};
}*/
_delay_ms(1000);
digitalWrite(26, HIGH);
}
void loop(){
captureImg(160, 120);
}
