USB Serial Communication Continuous

[mister_e]

I've never tried with a DEFINE OSC 20... but i think it's the main problem.

Look how i did it in mine. (config fuse as well)

and now

DoLow:
LOW PORTC.0
USBSERVICE
PAUSE 30
USBSERVICE
return

This example don't use instant interrupt, inserting a PAUSE and using On INTERRUPT GOTO might cause some problem for the USBSERVICE.

next point...i don't know what's happen if you use both HSER_BAUD and HSER_SPBRG together... Assuming HSER_SPBRG may override the HSER_BAUD, you have a big problem as your SPBRG value is way out of range @20MHZ... but good @8MHZ.

to have 2400 baud @20MHZ, you should use...

DEFINE HSER_RCSTA 90h ' Enable serial port & continuous receive
DEFINE HSER_TXSTA 20h ' Enable transmit, BRGH = 0
DEFINE HSER_SPBRG 129 ' 2400 Baud @ 20MHz, 0.17%
DEFINE HSER_CLROERR 1 ' Clear overflow automatically

I do believe the HSER_CLROERR may help a little bit.

There's probably something else... i feel a bit lazy today