Hello,

I'm trying to program a PIC 18F2455 chip. I'm using PicBasic Pro as a
frontend, MPLab v7.30 for the assembler, and MPLab icd 2 for the
programmer. A simple testing program to flash a light on and off at 1
second intervals instead takes 8 seconds:

----------------------------------------
INCLUDE "modedefs.bas"

define OSC 8

TRISA=%00000
TRISB=%00000000
TRISC=%11111111

StatusLED	VAR porta.1

LOOP:
  high StatusLED
  pause 1000
  low StatusLED
  pause 1000
  goto LOOP
------------------------------------------

If I change OSC to 4 (or leave it out), the program takes 4 seconds
per transition, so I initially thought I could just set OSC to 1 and
be done with it - this wouldn't compile in PicBasic Pro, however,
giving me the error "Symbol not previously defined (PAUSEUSL)".

I tried fiddling with some of the constants defined in
C:\pbp\p18f2455.inc, which the generated assembly included:
--------------------------------------------
   INCLUDE "P18F2455.INC"  ; MPASM  Header
        __CONFIG    _CONFIG1L, _PLLDIV_5_1L & _CPUDIV_OSC1_PLL2_1L &
_USBDIV_2_1L
        __CONFIG    _CONFIG1H, _FOSC_HSPLL_HS_1H
        __CONFIG    _CONFIG2H, _WDT_ON_2H & _WDTPS_128_2H
        __CONFIG    _CONFIG3H, _PBADEN_OFF_3H
        __CONFIG    _CONFIG4L, _LVP_OFF_4L & _XINST_OFF_4L
---------------------------------------------

Unfortunately, nothing there seemed to have any effect on the timing
at all. Where do you suggest I look next? I'm at a bit of a loss.

(It's important that the timing be right for this, as I need to use
serial comms to load new data at runtime, and SERIN doesn't seem to
want to work, even when I tried setting the baud rate on the other end
of the serial to 1200 to compensate.)

Please let me know if I've missed describing anything important, I'm
still quite new to PIC programming.

Cheers,
Mark

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