>
> I have a Optrex LCD attached to a PIC16C54
> ra.0    Enable Bit on Disp.
> rb.0    DB0
> rb.1    DB1
> rb.2    DB2
> rb.3    DB3
> rb.4    DB4
> rb.5    DB5
> rb.6    DB6
> rb.7    RS
>         R/W tied low
>         DB7 tied low
>
> I just want to transmit one character to it and I can't get to work.

One problem is that you won't be able to use the display with the wires as
you have indicated them.  You MUST have DB4-DB7 to access the display at all,
and you need DB0-DB3 as well if you want to use 8-bit mode rather than 4-bit
mode.  I'd suggest you pinout your display as:

RB0: E
RB1: RS
RB2-3: Use for whatever you want
RB4-RB7: DB4-DB7

and then use the display in 4-bit mode.