LH loads 16 bits and extends the sign bit through the register. ICM loads selected 8 bit bytes per the mask. Is there a LLH Load Logical Halfword?
On Wed, Aug 6, 2025 at 10:40 AM Charles Mills <[email protected]> wrote: > On Wed, 6 Aug 2025 05:42:55 -0400, David Cole <[email protected]> wrote: > > >Why use B in one case and C in the other? > > I see what you are asking. Why 'B'? I don't know. Does any other opcode > use B for Byte? Lots of C's: MVC, CLC, ICM, STC, ... > > I agree -- LC would have made more sense. Other than it might be construed > as or reserved for Load Complement; analogous to LCR. > > Charles > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO IBM-MAIN > -- Mike A Schwab, Springfield IL USA Where do Forest Rangers go to get away from it all? ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
