On Wednesday, 23 September 2020 at 22:33:38 -0400, Clem Cole wrote: > Dave: Seymour used ones complement on the 3000 and 6000 series. > Maybe there? The primary HLLs I used on the CDC boxes were FTN and > Pascal, but I would not be surprised if that was were you saw it. I think most of the bigger pre-IBM 360 machines used one's complement. Didn't the PDP-10? I knew it not only from the CDC 3200 and 3800, but primarily from Univac (1108 and 494). The Univac techies explained to me that the primary arithmetic function was subtraction; addition was subtracting the complement. And that worked faster with one's complement. Greg -- Sent from my desktop computer. Finger grog@lemis.com for PGP public key. See complete headers for address and phone numbers. This message is digitally signed. If your Microsoft mail program reports problems, please read http://lemis.com/broken-MUA