8-Bit Software

The BBC and Master Computer Public Domain Library

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Submitted by Steve Fewell


Call OSBYTE #&86 to obtain the Text cursor position. After this call, X contains the horizontal position of the cursor
(POS) and Y contains the vertical position of the cursor (VPOS).
Set A to Y (VPOS value) and jump to &AE18 to set the IWA to the 1-byte value in A and exit.

Disassembly for the VPOS routine

AABC   169 134 A9 86 LDA#&86
AABE   032 244 255 20 F4 FF JSR &FFF4 OSBYTE
AAC1   152 98 TYA
AAC2 L 076 024 174 4C 18 AE JMP &AE18 Set IWA to 8-bit value in A


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