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BBC Micro Elite

Utility routines: CLYNS (6502SP version)

Name: CLYNS [View in context] Type: Subroutine Category: Utility routines Summary: Clear the bottom three text rows of the mode 1 screen by sending a #clyns command to the I/O processor
Returns: A A is set to 0 Y Y is set to 0 Other entry points: SC5 Contains an RTS
.CLYNS LDA #%11111111 \ Set DTW2 = %11111111 to denote that we are not STA DTW2 \ currently printing a word LDA #%10000000 \ Set bit 7 of QQ17 to switch standard tokens to STA QQ17 \ Sentence Case LDA #21 \ Move the text cursor to column 1, row 21 STA YC LDA #1 STA XC LDA #clyns \ Send a #clyns command to the I/O processor to clear JSR OSWRCH \ the bottom three text rows of the top part of the JSR OSWRCH \ screen LDA #0 \ Set A = 0 TAY \ Set Y = 0 .SC5 RTS \ Return from the subroutine