PDP-12 at the RICM

ben bfranchuk at jetnet.ab.ca
Wed Jul 15 00:06:11 CDT 2015


On 7/14/2015 10:22 PM, Fred Cisin wrote:
>>  The 8086 had four segment registers:
>>     CS    - Code segment, used with IP register
>>     DS    - Data segment
>>     SS    - Stack segment, used with SP and BP registers
>>     ES    - Extra segment, used with DI for string instructions as
>>           destination (DS:SI as source)
>>  You could override instructions dealing with memory with any of the
>> segment registers:
>
> If you were writing an emulator, what would you have it do if an
> interrupt occurred while in a REP operation with a segment override?
>
> Just how accurately should an emulator match the behavior of the
> emulated processor?
>
Halt and catch fire ... No that's 6800's.






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