salam dear,

i m currently working on MT8816 8*16switch array to design a PBX system.
if u have any difficulty then mail me at muhammadfaisal_pk@hotmail.com.

the simple solution for MT8816 is that:

1)connect the addresses and data pin to ant port of 889c52 directly.

2)address select the particular switch and data 1 or 0 make the selected switch on or off

2)make sure at the time of address sending and data (address coding to select the particular switch is given in the data sheet )data must be low and then give a pulse to data e.g setb data and clr data to on or off the switch.

for further ino mail me
ALLAH HAFIZ