Re: Hires - to - Lores ... Yikes

[mjmahon@aol.com (Michael J. Mahon)]

cranem@[nospam]aol.com replied:

>My 6502 code is a *bit* rusty these days, but I think this would do
>the job.  If I'm wrong about the ROL opcode, replacing it with a
>simple LDA #$40 would do the job at the expense of being twice the
>size (but being more generic).
>
>                                 LDA #$20     ;%00100000
>                                 STA $0304
>                                 ROL              ;%01000000
>                                 STA $0307
>300- A2 00                LDX  #$00
>302- BD 00 20           LDA $2000,X
>305- 9D 00 04           STA $0400,X
>308- E8                      INX
>309- D0 F7                BNE $0302
>30B- EE 04 03           INC $0304
>30E- EE 07 03           INC $0307
>311- AD 07 03          LDA $0307
>314- C9 08               CMP #$08
>316- D0 E8               BNE $0300
>318- 60                     RTS

I'd definitely recommend the LDA--that value is one of the
things someone might want to change!

-michael

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