Hello to everyone !
I am currently working on a portable radio project using TEF6686 tuner module using PIC18F26K22 and a SPI LCD module EADOGM 132.
My issue is as follows:
If I try to read data from the TEF6686 on I2C bus, I can hear the data transaction in the speaker on some certain signal level conditions on FM band/AM band.
On really weak stations there is no I2C bus noise, on strong stations there is no noise. Only on some intermediate signal level, the bus activity can be heard and is annoying.
On AM band is really a disaster. If there is no bus activity, all gets quiet, but the problem is that I want to read signal quality and RDS data (on FM band) to print on display.
If I disable slew rate control then is really a mess. With slew rate limit on, there is some improvement, but not too much.
Could this be a slew rate problem ?
I have seen some videos on youtube with people using Arduinos and they didn't seem to have this issue., even using breadboards with long wires going everywhere.
My circuit is made on a small PCB and layed out pretty well, I think.
Should I consider trying out some other micro ? I was looking at the 18F26K42 and that seemed interesting, it has some registers for configuring the I2C slew rate, but I have no idea if that would do much...
What is your opinion, am I missing something ?
I am currently working on a portable radio project using TEF6686 tuner module using PIC18F26K22 and a SPI LCD module EADOGM 132.
My issue is as follows:
If I try to read data from the TEF6686 on I2C bus, I can hear the data transaction in the speaker on some certain signal level conditions on FM band/AM band.
On really weak stations there is no I2C bus noise, on strong stations there is no noise. Only on some intermediate signal level, the bus activity can be heard and is annoying.
On AM band is really a disaster. If there is no bus activity, all gets quiet, but the problem is that I want to read signal quality and RDS data (on FM band) to print on display.
If I disable slew rate control then is really a mess. With slew rate limit on, there is some improvement, but not too much.
Could this be a slew rate problem ?
I have seen some videos on youtube with people using Arduinos and they didn't seem to have this issue., even using breadboards with long wires going everywhere.
My circuit is made on a small PCB and layed out pretty well, I think.
Should I consider trying out some other micro ? I was looking at the 18F26K42 and that seemed interesting, it has some registers for configuring the I2C slew rate, but I have no idea if that would do much...
What is your opinion, am I missing something ?
