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Utility routines: DELAY

[BBC Micro disc version, Docked]

Name: DELAY [Show more] Type: Subroutine Category: Utility routines Summary: Wait for a specified time, in 1/50s of a second
Context: See this subroutine in context in the source code Variations: See code variations for this subroutine in the different versions References: This subroutine is called as follows: * BRIS calls DELAY * DKS3 calls DELAY * dn2 calls DELAY * DOENTRY calls DELAY * GTNMEW calls DELAY * Main game loop (Part 5 of 6) calls DELAY * TT217 calls DELAY

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