SPP for Digilab

[2door]

Hi everyone,
I have to work on a project involving Digilab DIO2/D2E boards. The
problem is that I have to design using VHDL language a controller for
the SPP between the computer and the boards. The thing I have to do is
to send a STROBE signal from the PC to the board and after that to send
some data and display it on the LED segment. The board has to send me
back an ACK or ERROR signal back,
The thing is I don`t know how to make the controller for the parallel
port in order to do the mentioned things above.
Pleas help me in some way if possible and write me for more details.

 

Look up state machines in your textbook. This is an ideal application
for a state machine. To properly design the state machine you must
define in detail what must happen for the data transfer including what
to do when the logic sees ACK or ERROR. You mentioned a strobe, but
from your description it sounds more like a signal that is requesting
to send data. If it were a strobe you would probably have the data
already on the output and then strobe it in.

This would probably not be a very complex state machine, but it is a
good problem for you because it is much more realistic that many of the
homework problems presented on this forum. When you have made a start
on working it out and if you are still having problems let us know what
you have done and what the problem is. Remember, the first step is a
detailed description of the data transfer process.

Charles