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Re: Opcode Instruction Question



Bryan Parkoff wrote:
> 
>     I think that the word Program Status and Processor Status can be
> confusing to us.
>     My point is that Processor Status is probably the same as Program Status
> which it is not part of the register.  Processor Status is 8-bit for 65xxx
> because it has only 7 or 8 flags.  I do not discuss general information
> which are opcodes, operands, variables, etc.
>     Please try to answer my question below.
> 
>     How many flags and 8/16/32 bits in Processor Status do Intel, 68K,
> PowerPC, Z80, 8080, other microprocessors have?  It is very clear question.
> Please advise.
> 
> --
> Yours Truly,
> 
> Bryan Parkoff
> BParkoff@satx.rr.com

This is sounding suspiciously like homework....

The VAX 
Processor Status Longword
bits
3322222222221111|1111110000000000
1098765432109876|5432109876543210
x	        |		  - compatibility mode
 x              |                 - trace fault pending
  --            |                 - not used
    x           |                 - instruction 1st part done
     x          |                 - exec on interrupt stack
      xx        |                 - current access mode
        xx      |                 - privious access mode
          -     |                 - not used
           xxxxx|                 - interrupt priority level
                |-------          - not used
                |       x         - decimal overflow trap enable
                |        x        - floating underflow fault enable
                |         x       - integer overflow trap enable
                |          x      - trace fault enable
                |           NZOC  - negative, zero, overflow, carry


Anybody do SPARC ?

Jim