On Fri, 19 Jun 2026 14:05:30 +0000, Seymour J Metz wrote: > ... >The ASCII bit in the PSW is the to modify the behavior of decimal >instructions; it has no relevance to telecommunications access methods, which >support a variety of character sets. > Did that affect anything other than the representation of the sign nybble? After UNPK wasn't OC x'F0' or OC x'30' still necessary? Did any software inspect that PSW bit to choose which?
Why was that ASCII mode valuable? was there a library of signed decimal (tape?) data needing compatibility support? TCU hardware? -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
