I have 3 cards (micro controllers), one is master and other two are slaves. The inter processor communication is through the data bus. The master can send commands to slaves and can receive acknowledgment from slaves.
I am writing program for that. Description of my work is as follows.

The embedded control system consists of a personnel computer, three identical
microcontrollers and three stepper motor drivers.
The personnel computer is connected to one of the microcontrollers through a serial link. This microcontroller is the master subsystem and all other microcontrollers are slave subsystems. The master subsystem can send data to slave subsystems through the data bus. Similarly it can receive data from the
slave subsytems. But slave subsystems have no privilege to access the master's data bus.

I planned to implement this communication using handshake signals. So it is very important for me to know the timing details of ports.
Prasad