I wondered if it was fair to list the DEC 23B00A2, etc that hold the ucode as separate parts; they might have been a bunch of 256x4 PROMs, and the separate part numbers were just for the different programming. (Whether differently programmed PROMs count as 'different' parts for the purposes of this table I leave aside.) Looking at my M7232 card, though, I think they may be masked ROMs; the only part number on them looks like a manufacturer applied one with the DEC number. Interestingly, about a third are MMI parts, and the rest are NS. I wonder if neither manufacturer had enough capacity alone, or if DEC just wanted multiple sourcing. (The parts appear to be basically the same, in terms of speed, format, etc so it appears either could have provided any of them, modulo the programme.) Noel