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Elite on the BBC Micro and NES

Drawing the screen: CLYNS

[6502 Second Processor version]

Name: CLYNS [Show more] Type: Subroutine Category: Drawing the screen Summary: Clear the bottom three text rows of the mode 1 screen by sending a #clyns command to the I/O processor
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: * dockEd calls CLYNS * EQSHP calls CLYNS * hm calls CLYNS * JMTB calls CLYNS * qv calls CLYNS * TITLE calls CLYNS * TT219 calls CLYNS * SCAN calls via SC5

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