Evading the disk check Re: Weird idea re Print Shop

[Steve Nickolas <lyricalnanoha@usotsuki.hoshinet.org>]

Remember that I'm working from the code on an already cracked disk - the 
triple NOP is probably a disabled JSR.  This is the first part of the 
checkpoint; the second is the function at 77B6 which I have not yet 
analyzed.

Simply removing the code from 77FE to 7804, or from 77F9 to 7804, causes a 
crash into the monitor - so there's something else up here.  The code is 
in MENULIB.

-uso.

0077F9           isPSDisk:
0077F9  A9 01              LDA  #1
0077FB  20 B6 77           JSR  sub_0_77B6
0077FE  B0 0F              BCS  loc_0_780F
007800  D0 0D              BNE  loc_0_780F
007802  C0 02              CPY  #2
007804  F0 09              BEQ  loc_0_780F
007806  EA                 NOP
007807  EA                 NOP
007808  EA                 NOP
007809  A9 00              LDA  #0
00780B  8D 1E 70           STA  byte_0_701E
00780E  60                 RTS
00780F           loc_0_780F:
00780F  20 C6 74           JSR  sub_0_74C6
007812  20 D3 6E           JSR  sub_0_6ED3
007815  AD 1E 70           LDA  byte_0_701E
007818  F0 03              BEQ  loc_0_781D
00781A  20 03 8E           JSR  $8E03      ; clear window
00781D           loc_0_781D:
00781D  A2 61              LDX  #$61       ; message is
00781F  A0 78              LDY  #$78       ; "place PS disk
007821  20 06 8E           JSR  $8E06      ;  back in drive"
007824  20 05 80           JSR  sub_0_8005 ; press key to cont.
007827  4C F9 77           JMP  isPSDisk