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Elite on the BBC Micro and NES


[6502 Second Processor version]

Name: ZZAAP [Show more] Type: Subroutine Category: Demo Summary: Draw a vertical red laser line from (128, 67) to (128, 160)
Context: See this subroutine in context in the source code References: This subroutine is called as follows: * DEMON calls ZZAAP
.ZZAAP LDA #RED \ Send a #SETCOL RED command to the I/O processor to JSR DOCOL \ switch to colour 2, which is red in the space view LDA #128 \ Set X1 = 128 STA X1 STA X2 \ Set X2 = 128 LDA #67 \ Set Y1 = 67 STA Y1 LDA #160 \ Set Y2 = 160 STA Y2 JMP LL30 \ Call LL30 to draw a line from (X1, Y1) to (X2, Y2), \ returning from the subroutine using a tail