Hi
I’m running a stand-alone 328 processor at 8Mhz, ( running at 3.3v) external Crystal , using the mini core for both bootloader and uploading programs . This works fine and I can print stuff on the serial monitor at 19200 baud .
But !!
I have a Rf solutions device that is fine with the processor at 16Mhz and this baud rate but won’t run at 8Mhz and the same baud rate.
Wondering if there is an issue somewhere with this combination ??
Are you running 3.3v at 16MHz or 5V? If you are running at 5V it could be a voltage level problem rather than a baud rate problem.
No
I’ve run 16Mhz from a UNO at 5v with voltage divider to 3.3 volts .
I’ve run 8Mhz at 3.3 v into the RF solutions zeta + which is a 3.3v device .
Two online sources put the error at 0.2% (19231 vs 19200) when the processor is running at 8 MHz. Same for 16 MHz.
Does the rf solution device communicate to the serial monitor?
Yes , via a UART to usb .
So did you test your stand alone 328 at 16mhz, or use a different board for the 16mhz test?
I was thinking this was a baud rate issue - maybe not .
Think I need to go over this again (lot day today !)
The RF solutions device is not programmed except to set it up, it’s really a UART radio bridge , so just serial input .
This was a wiring mistake !! I miss interpreted the data sheet and put it to sleep.
A further “ mistake” on the transmitter end corrected that end - hence lots of confusion as I thought both were identical !
Hope that makes some sense lol