Hi,

I'm using the Microchip C18 compiler, and a PIC18F452 to relay RS232
serial data from a host computer to a serially controlled CCTV camera.
I'm using the hardware USART on RC6/RC7 to communicate with the PC, and
this works fine.

Now I'm trying to use the C18 'Software UART' library functions to
implement a software UART on RD6/RD7.

Trouble is, the C18 manual says you (the user) has to define the
following delays:
        DelayRXHalfBitUART  as ((((2*FOSC/(4*baud))+1) / 2)- 12 cycles
        DelayRXBitUART         ((((2*FOSC/(8*baud))+1) / 2)- 9 cycles
        DelayTXBitUART         ((((2*FOSC/(4*baud))+1) / 2)- 14 cycles

I guess these routines would need to be written in assembler to be
accurate (?) and my assembler is pretty poor, so I'm looking for any
kind soul who have already done this, and can send me some pointers or
sample code.

(My system clocks at 4 Mhz with 4x PLL enabled = 16 Mhz, and the comms
is running at 4800 baud)

Thanks, Peter Moreton

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