IF _BUG_FIX .wsstatecopy EQUB 0 \ We store a copy of the wstate here so we know which \ state to switch back to after printing .SwitchToCharSet \ This routine switches the MOS character definitions \ into memory at &C000 on a BBC Master LDA #0 \ Call OSBYTE with A = 0 and X = 1 to fetch bit 0 of the LDX #1 \ operating system version into X JSR OSBYTE CPX #3 \ If X =< 3 then this is not a BBC Master, so jump to BCC char1 \ char1 to continue drawing the character LDA wsstate \ Copy wsstate into wsstatecopy STA wsstatecopy JSR savews \ Call savews to put the character set in the correct \ place .char1 LDA K3 \ Set A to the character to print RTS \ Return from the subroutine ENDIFName: SwitchToCharSet [Show more] Type: Subroutine Category: Utility routines Summary: Switch the MOS character definitions into memory at &C000 on a BBC MasterContext: See this subroutine in context in the source code References: This subroutine is called as follows: * tube_wrch calls SwitchToCharSet
[X]
Configuration variable OSBYTE = &FFF4
The address for the OSBYTE routine
[X]
Label char1 is local to this routine
[X]
Configuration variable savews = &DD06
The address for the savews workspace routine from the loader so we can call it to ensure the MOS characterdefinitions are loaded before printing text on the BBC Master
[X]
Configuration variable wsstate = &DDBA
The address for the wsstate workspace routine from the loader so we can call it to ensure the MOS characterdefinitions are loaded before printing text on the BBC Master
[X]
Variable wsstatecopy is local to this routine
We store a copy of the wstate here so we know which state to switch back to after printing