MY SERIAL TEST CODE WORK PERFECT IN 4 MHZ OSC AT 2400 BAUD BUT MY ORIGINAL CODE NEED WORK AT 19200 I DEFINE OSC 20 AT PROGRAMMING TIME I SET XT OSC IN MPLAB CONFIG. BITS BUT MI CODE DONT WORK WITH 20 MHZ, I CHANGE PARAMETERS FOR 9600 BAUD 8 MHZ AND STILL DONT WORK I CHECK MANUAL PAGE 50 BIT 3 IN OSCCON REGISTER AND CONFUSED ME, IS READ ONLY AS 1 BUT NOTE 1 SAY RESET TO 0 WHEN USING Two-Speed Start-up and Fail-Safemode is enabled, SOUND LOGIC TO ME BUT WHY RESET TO 0 WHEN USING LP, XT or HS THIS MODES ARE EXT OSC. AND WHEN BIT 3 RESET TO 0 = Device is running from the internal oscillator... ANY HELP PLEASE