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Drawing the screen: DOVDU19

[6502 Second Processor version]

Name: DOVDU19 [Show more] Type: Subroutine Category: Drawing the screen Summary: Change the mode 1 palette by sending a #SETVDU19 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: * DEMON calls DOVDU19 * HALL calls DOVDU19 * LOOK1 calls DOVDU19 * TITLE calls DOVDU19 * TRADEMODE calls DOVDU19 * TT22 calls DOVDU19 * TT23 calls DOVDU19 * WHITETEXT calls DOVDU19

Arguments: A The colour number to define
.DOVDU19 PHA \ Store A, the colour number, on the stack LDA #SETVDU19 \ Set A to #SETVDU19, ready to write to the I/O \ processor BNE label \ Jump to label to write #SETVDU19 <colour> to the I/O \ processor, returning from the subroutine using a tail \ call (this BNE is effectively a JMP as A is never \ zero)