On 1/15/25 09:49, Paul Koning wrote:
Yes, it certainly had that feature. I'm not sure
about the limits, I thought the integer limit was 99 digits. The reason for these options
is that it's directly supported by the hardware, which has arbitrary length integers
and (up to a limit I forgot) floating point mantissas. Given the encoding in the
hardware, it makes sense that you could mix and match; the hardware would accept operands
of whatever size you pick, in whatever combination you like. So, for example, adding a 3
digit integer to a 300 digit integer would work just fine.
Looked up the latest 1620 FORTRAN reference in the Monitor II-D manual.
10 and 28 for FANDK, so my memory isn't completely gone yet.
Always wondered if addition and subtraction on the 1620 had a
"shortstop" implementation. For example, adding a 10 digit to a 50
digit number, would the operation stop if there was no carryout after 10
digits, or would the implementation process all 50 digits?
--Chuck