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- .xdef _rowread
- .text
- _rowread:
- | Write the mask to the port
- move.w %d0,0x600018
- | Wait for a few milliseconds until the I/O can return a valid value
- moveq #24,%d0
- 0:
- dbra %d0,0b
- | Read the port and write it to %d0 (return value register)
- move.b 0x60001B,%d0
- | Invert the byte
- not.b %d0
- and.w #0xFF,%d0
- | Return
- rts
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