Alexander, thanks. I found the manual. And there they are: Reader Start DC1 ^Q Punch Start DC2 ^R Reader Stop DC3 ^S Punch Stop DC4 ^T Now I can confirm that my disassembly is pretty accurate. :-) Thanks :-) -- Linux Home Automation Neil Cherry kd2zrq@linuxha.com http://www.linuxha.com/ Main site http://linuxha.blogspot.com/ My HA Blog Author of: Linux Smart Homes For Dummies KD2ZRQ