PLCC44 - yes, I believe so.

I've looked at that MAX232 part and I don't think it is what I need. It would appear to be something that converts a UART output to a +/- 12V type signalling. I want to convert 5V -> 3.3V. I think a couple of resistors can acheive this. Once I have some method of outputting to the 8051 UART, (need to write some SBUF code), I can stick a scope on the pins and see what is coming out. The code that is there at the moment, which is commented out, appears to be reading the port and is, thus, useless in this regard.


The drawing is a very large sheet of thick, heavy paper, over 1m square. I cannot scan it. Even if I could, I doubt I'd be allowed to release it. Where it has been folded in the past, some of the information is no longer readable.


The cable from the socket on the PCB to where the module will be mounted will be about 300mm - from my reading, I think it will be fine.

I doubt there is budget to justify re-writing the application. I am not confident enough with the hardware to change anything. If it was just the 8051, then maybe.

There is a great amount of code in the app that I don't understand. It is setting up a load of stuff, and managing timing between the 8051 and a huge DSP chip which has it's own crystal.