Hello every one,
Using Arduino Uno, I am trying to program a Samsung I2C tuner based on the SN761672A pll synthesizer ic and I need considerable help. I appreciate every bit of view, suggestions, and efforts as I am on crossroads confusion and hope your contributions are rewarded in success and relief. The code shows how far I’ve reached.
I summarize my objectives in setting the tuner to function (plug and play) like analog. The hardware is almost comprehended, but the software is complicated.
- Be able to write the read/write bytes to control the IC.
- Correctly setting the bits and bytes of registers.
- Be able to read the frequency and write it to the tuner.
I understood there are two Read Bytes: the ADB address byte and the SB status byte. I tended to adopt the default suggested in Table 3, page 9.
The Write Bytes are five:
ADV(0xC0: 11000000), DB1(0), DB2(0), CB(0xCA:11001010), and BB different.
Based on my understanding of the explanation and description of symbols in the datasheet, I set these bytes as in the code.
The I2C control part in the SN761672A is in pages 9, 10, 11.
I need some help to configure the divider byte DB1 and DB2. I understood from page 9 table 3 the default value is 0??
Programmable counter set bits N=N14…..N0 is my blackout I need help please!
If I could set the tuner to the VHF_L, read the frequency on power up, write and display the value (set /scan the frequency), then I went far well.
//Samsung TECC0949PG35A(AA40-00076A) TV\CRT tuner with SN761672A tuner IC . 21.01.2024
#include <Wire.h>
//I2C Read mode
#define ADB 0x60//Address Byte, read 1
#define SB 0xB8// Status Bit
//I2C Write mode
#define ADV 0xC0 //11000000, Address Byte, write 0
#define DB1 0x0//00000000, 0x0
#define DB2 0x0//00000000, 0x0
#define CB 0xCA//11001010
#define BBL 0x1//00000001, Band Switch, Low
#define BBH 0x2// 00000100, Band Switch, high
#define BBU 0x8//00001000, Band Switch, ultra
long frequency;//default frequency after power up
long freq_set;// set or scan +/- increment, decrement
long IF_freq = 31900000;// IF frequency 31.9MHz
//VHF_L 48-180MHz BandI
//VHF_H 160-470MHz BandII
//UHF 430-860MHz BandIII
#define L_bandbegin 48;//48 MHz
#define H_bandbegin 160;//
#define U_bandbegin 430;//
#define L_bandend 180;//
#define H_bandend 470;//
#define U_bandend 860;//
int step_rate1 = 1000000;//1MHz steps
int step_rate2 = 500;//500kHz
int step_rate3 = 100;//100kHz
void setup()
{
Serial.begin(9600);
Wire.beginTransmission(0x60);// Address Byte ADB
Wire.beginTransmission(0xB8);//SB Status bit
Serial.println(0x60);
delay(200);
Serial.println(0xB8);
delay(200);
Serial.println(" 3_Band Tuner ");
delay(200);
write_data();
}
void loop()
{
}
void scan_freq()
{
//freq_set = up_frequency + 1// increase/ decrease frequency
// while button + pressed
//if freq_set >= H_bandend;
{
//freq_set = L_bandbegin;
}
}
void write_data()
{
Wire.beginTransmission(0x60);
Wire.write(ADV);
Serial.println(ADV);
Wire.endTransmission();
}
I think it's the I2C bus not carrying out commands or distorted. I managed to trace the I2C bus to the tuner it's shiny and new or nice and clean. There's no IF signal coming out of the tuner, or may be it's too weak to come out of the SAW filter. I don't have datasheet for it and the TV monitor schematics I get suggested have different tuners. So, hopefully getting IF signal will solve the problem.
