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|    Message 2,633 of 4,255    |
|    mutazilah@gmail.com to Joe Monk    |
|    Re: PDOS/86    |
|    15 Jul 21 18:48:27    |
      From: muta...@gmail.com              On Friday, July 16, 2021 at 10:56:55 AM UTC+10, Joe Monk wrote:              > > The same way that z/Arch running in AM64 executes       > > a LR R3,R4 perfectly fine.       > >       > > So too the 80386 will execute "mov ax, bx" perfectly fine,       > > in exactly the same manner as the 8086.       > >       > > At least I think it will. I'm more familiar with S/3X0       > > assembler than x86.              > On an S/370, an LR R3,R4 is a 32-bit move. Same for S/390, and z/Arch.       >       > On an 8086, a mov ax,bx is a 16-bit instruction. Same on the 80386. In PM32,       that register is called EAX. AX only references the lower 16 bits of EAX.       >       > See the problem? They're not the same operations.              In the same way that z/Arch supports both 32-bit and 64-bit operations,       the 80386 supports both 16-bit and 32-bit operations.              You can do a mov ax, bx on both the 8086 and the       80386 (even in normal PM32, forget RM16, forget       V8086).              Or am I missing something?              BFN. Paul.              --- SoupGate-Win32 v1.05        * Origin: you cannot sedate... all the things you hate (1:229/2)    |
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