From: utzoo!watmath!csc
Newsgroups: net.micro
Title: 8255 info request
Article-I.D.: watmath.4340
Posted: Thu Jan 13 17:16:00 1983
Received: Fri Jan 14 00:03:10 1983

Help! I am trying to get one 8255 to talk to another, in mode 1.
The sender should receive an interrupt after the receiver has read his data,
and the receiver should receive an interrupt from its 8255 indicating data is
ready to be read.

The current plan looks like this:
(*OBF == negative true Output Buffer Full
 *ACK == negative true ACKnowledge
 *STB == negative true STroBe
  IBF == Input Buffer Full)

8255 in mode 1 sending data                           8255 in mode 1 receiving

                      |                                  |
              *OBF(b) |--------------------------------->|  *STB(a)
                      |                                  |
                      |                                  |
              *ACK(b) |<----------