.WSCpars EQUB 2 \ Transmit 2 bytes as part of this command EQUB 2 \ Receive 2 bytes as part of this command EQUW 0 \ This is unused as no parameters are transmitted along \ with this command .WSCAN PHX \ Store X and Y on the stack so we can restore them PHY \ later LDA #wscn \ Set A in preparation for sending a #wscn command LDX #LO(WSCpars) \ Set (Y X) to point to the parameter block above LDY #HI(WSCpars) JSR OSWORD \ Send a #wscn command to the I/O processor to wait for \ the vertical sync PLY \ Restore X and Y from the stack PLX RTS \ Return from the subroutineName: WSCAN [Show more] Type: Subroutine Category: Drawing the screen Summary: Ask the I/O processor to wait for the vertical sync by sending a #wscn command to the I/O processorContext: 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: * DELAY calls WSCAN * DK4 calls WSCAN * Main flight loop (Part 13 of 16) calls WSCAN * TT16 calls WSCAN
This routine sends a #wscn command to the I/O processor to ask it to wait for the vertical sync.
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Configuration variable OSWORD = &FFF1
The address for the OSWORD routine
[X]
Variable WSCpars is local to this routine
Transmit 2 bytes as part of this command
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Configuration variable wscn = 243
The OSWORD number for the #wscn command