5.25" PROM MisMatch Between II+ & IIgs

["Bryan Parkoff" <BParkoff@satx.rr.com>]

    I find an interesting disasembly that is not doing correct.  For
example: BEQ should be even and BNE should be odd.  Look at my code below.
I have copied PROM from Apple II+ to Apple IIgs for testing.

C600: A2 20        LDX #20
C602: A0 00        LDY #00
C604: A2 03        LDX #03
C606: 86 3C        STX 3C
C608: 8A           TXA
C609: 0A           ASL
C60A: 24 3C        BIT 3C
C60C: F0 10        BEQ C61E {+10}
C60E: 05 3C        ORA 3C

    On Apple II+, 6 is even.  BEQ should state, "6 is equal to even".  BEQ
should report TRUE, but Apple II+ reports false.  Apple IIgs reports true.
C60E is not supposed to be executed on Apple II+, but Apple IIgs did execute
C61E.
    Please compare my example on your both real Apple II+ and Apple IIgs.
It is possible that emulator is not doing correct for manipulating odd and
even like using to test PARITY.


--
Yours Truly,

Bryan Parkoff
BParkoff@satx.rr.com