In order to save the cost of a crystal, I would like to be able to run the AN2295 bootloader in with the interanal RC oscilator calibrated t0 36 khz and, if possible, communication at a bitrate of 115200.
My PCB features a QE128 and a 4Mhz crystal.
Currently, the internal RC oscillator is calibrated to 32.768 kHz and the bootloader runs at a fast enough 38400. However, the usercode needs 115200, and therefore, the user code use the 4Mhz crystal instead, since 32.768 can't be used to generate 115200.
However, If I calibrate the internal RC- oscillator to 36 kHz, I can set the usercode generate 115200 from it (done through PE). If I do that however, the bootloader will not generate its 38400.
In essence, I have no need a bitrate of 115200 in the bootloader. I do however need it to operate correctly with a 36khz (or other frequency that can be used for 115200 in user code) internal oscillator speed.
Have I made myself clear enough?
Can this be done at all?