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GPL Status Byte


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Okay, the GPL status byte at >837C is giving me grief.


Thy Hallowed Book of Truth sayeth that thy Holy GPL Byte of Holy Status be it assembled thusly:




And lo, it was so.


Yet hark, verily does thy Book Of Truth refer to an "equal bit" (FCOM, page 260):




Where ist thou "equal bit"?


[ or is the book referring to the eq bit in the 9900? If so, it's a bloody shambles! ]

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Thanks Lee. Well, the plot thickens... I found this in the ROM after single stepping:


0FAC MOV R2,@>837C


In other words, the GPL status byte is a copy of the 9900's status register.


Well well...


The EQ bit in the 9900 is bit 2, which just happens to be the COND bit in GPL parlence. So, you're spot on sir! Thank you. Another mystery solved.



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