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Elite on the BBC Micro

Utility routines: DELAY (6502SP version)

Name: DELAY [View in context] Type: Subroutine [Compare versions] Category: Utility routines Summary: Wait for a specified time, in 1/50s of a second
Wait for the number of vertical syncs given in Y, so this effectively waits for Y/50 of a second (as the vertical sync occurs 50 times a second). Arguments: Y The number of vertical sync events to wait for
.DELAY JSR WSCAN \ Call WSCAN to wait for the vertical sync, so the whole \ screen gets drawn DEY \ Decrement the counter in Y BNE DELAY \ If Y isn't yet at zero, jump back to DELAY to wait \ for another vertical sync RTS \ Return from the subroutine