We used IBM PC/AT as a main controller on each side of video conference system, used 北工大's Z80 controlling board to hand cook those assembly codes. We designed signal control board, RGB color component memory boards, video signal AD/DA control board. Used software and patented algorithm to code/decode image data in every frame ... All hardware and software were designed by our group, except IBM PC itself. In university lab, we worked on it for three versions, We were the first users in China to use email, internet, etc. at that time... 爽。