This is my first post here so please bear with me.
I have a design problem and the quickest solution would be to use the EPP feature.
I have a electronic device that has a 8bit bi-direction data bus, as well as 6 more inputs and 3 outputs.
My first idea was to interface this to a PIC16F877, transfer the data to SRAM (since this is a huge amount of data) and then transfer this to the computer via RS232 protocol.
This is a valid solution but it is too slow. It would take over 30seconds per one cycle and it is not acceptible.
Another idea was to do it all with one FPGA but this would take way to long and too much $$.
So I think that using a PIC to control most of the other input and outputs (for configuration purposes mostly) I would be able to use the EPP for 8 bit data in/out. And since the EPP has 3 spare inputs, they are a perfect match for the 3 outputs this device outputs.
The problem is that I can't seem to get the bi-directional 8 bit data bus to work. I have worked withthe parallel port before, using BASE + 0 for 8 bit output, BASE + 1 for 5 bit input and Base + 2 for additional 4 bit input for custom electronics.
I was wondering if anybody has a sample code (C/C++ or Qbasic) to be able to READ an 8 bit value from and external device using the b-directional data bus on the Extended Parallel Port. I read a lot of tutorials on the internet but they don't seem to help much.
any help would be appreciated.