Communication FROM the RCX TO the IR Tower/ PC

RCX to PC communication is difficult because of the tower hardware. The tower shuts off a few seconds after it completes transmission to save power. Messages from the RCX that arrive during or after the shut off are truncated or not received. The tower works best in request / reply mode where the PC requests something and the RCX replies to it. In request/ reply mode, a good practical cap on the max number of data bytes to transfer from the RCX to the PC is 256 (does not include header, complements, or checksum). Larger sizes may work, however data transmission might be truncated when the tower shuts off.