In article <52550040-57eb-4a48-9627-e5c6444fe...@googlegroups.com>, <foll...@gmail.com> wrote:
> I've got a copy of "IBM Operating System/360 Assembler Language" copyright > December 1964. Pretty sure all the opcodes listed in Appendix B (Machine > Instruction Mnemonic Codes) are still supported by the hardware (I haven't > checked 'em all). There are some 360/20-only codes that might not work. I recall a BAS and BASR, op codes 0D and 4D, that were the predecessors of the BAL and BALR instruction. Since the registers on the 360/20 were only 16 bits, they only saved the low-order 16 bits of the PSW for a return address (BAL/BALR store 32 bits, the bottom 24 of which are the return address). ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
