Sriharsha:

Another caution....

If this EPABX as you call it is supporting a large number of phone lines and local extensions (you mentioned 50 employees) then there is the likelyhood that the board you looked at with the 80C32 chip on it is just one slice of the system. Often these systems are configured for like 4 or 8 lines per board. If this is the case then there is probably another management processor someplace in the system. Most likely the software for that CPU would need digging into as well.

.... Makes the project even more questionable !!

Michael Karas