Just an idea, but have you considered using a serial ROM instead? Use the 
incoming byte as an address, and send the data out more-or-less directly. I 
see no reason why you couldn't include start and stop bits in the appropriate 
ROM bit positions. The only tricky bit would then be to generate the 
appropriate clock pulses for the ROM.

Just a thought.

Jake

On Sunday 14 August 2005 22:05, Peter van Hoof wrote:
> Oops, this time with the proper tag
>
>
> I'm going to be building a device that translates printer output from a
> Meiki injection molding machine which uses a special NEC printer (expensive
> wide dot matrix for which I cannot find a manual) to a RS232 pc connection
> or a more standard printer.
>
> The output I get on a standard printer is pretty close to what I need there
> are just a few characters that need to be replaced by others.
>
> The plan is to use a 16f877 with it's PSP connected to the printer
> connection collect characters use lookup table(s) then send out the
> modified stream back out thru RS232 or parallel thru some other I/O pins
>
> The amount of data is not that great ( screen of about 40*25 chars ) and as
> far as I can tell there are no graphic characters are sent.
>
> Are there any gotcha's you can think of , any hints or perhaps even a
> completely different way to do the same simpler.
>
> Changing the machine is not an option, I have to have a portable solution
> to print out data from a hundred or so machines.
>
>
> Any help would be appreciated.
> Peter van Hoof
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