Thank you for all PIC members who read my email. Now I am encouraged to design my control system as I planned. Yes, Bill. My system will look like this. +->Rx.PC1.Tx---->Rx.PC2.Tx--->Rx.PC3.Tx--->Rx.PC4.TX---...-->Rx.PC36.Tx--+ | | | __________ V +------------<----------------| Main PC |-<-------------------<---------+ __________ I am trying to write a control program that will control a multivision system, so called cubes. So I need to adjust brightness, contrast, tint and all bunch of stuff with PC. Thank you. Chunhee Song -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu