Re: Prodos Woes

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

Dave Althoff Jr wrote:

>Dave Althoff Jr (dalloff@gcfn.org) wrote:
>
>: If you're going to do this trick in ProDOS, what you need to do is load
>: the image into a safe place, then copy it to the text screen.  I haven't
>: tried this, but it should work:
>
>: 300: A9 00      LDA #$00
>:    : 85 06      STA $06
>:    : 85 08      STA $08
>:    : A9 04      LDA #$04
>:    : 85 09      STA $09
>:    : A9 60      LDA #$60
>:    : 85 07      STA $07
>: 30E: A0 00      LDY #$00
>: 310: B1 06      LDA ($06),Y
>:    : 91 08      STA ($08),Y
>:    : C8         INY
>:    : D0 F9      BNE $0310
>:    : E6 07      INC $07
>:    : E6 09      INC $09
>:    : A9 08      LDA #$08
>:    : 18         CLC
>:    : C5 09      CMP #$09
>: 320: 90 EC      BCC $030E
>:    : 60         RTS
>Update:
>I have now tried it and it doesn't work.  Silly me, I BCC'ed when I should
>have BCSed...it only moves the first 256 bytes.  Fix it by changing:
>
>320:B0 EC       BCS $030E
>
>I've fixed the part below.  I also tested it...it works.
>
>: You can punch in and save as follows:
>
>: ]CALL -151
>: *300:A9 00 85 06 85 08 A9 04 85 09 A9 60 85 07 A0 00 B1 06 91 08 C8 D0 F9
>: *:E6 07 E6 09 A9 08 18 C5 09 B0 EC 60
>: *3D0G
>: ]BSAVE MOVER,A$300,L$24
>
>: ...then in the BASIC...
>: nnnnn PRINT CHR$(4);"BLOAD MOVER"
>: nnnno PRINT CHR$(4);"BLOAD TEXTSCREEN,A$6000":CALL 768
>: nnnnp WAIT 49152,128:GET K$
>
>Once I changed the comparison at 320, it worked.

And it still clobbers the screen holes.

If clobbering the holes is acceptable (!), then bracketing the BLOAD
with a couple of POKEs to the ProDOS memory map will do it.  (Or
just one POKE if you don't mind leaving low memory unprotected.)

-michael

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