REM > S/SerFix
REM Fixes double-null problem with MOS 5.00
:
Ver$="0.10":start%=&FFFF0380:DIM mcode% &400:SerInID=1
INSV=&22A:RMV=&22C:CNPV=&22E:OSBYTE=&FFF4:OSARGS=&FFDA:OSVEC=&FFB6
:
zp=&A8:PtrBlk=&80:InPtr=PtrBlk:OutPtr=PtrBlk+2:Temp=PtrBlk+4
:
FOR P=0 TO 1
O%=mcode%:P%=start%
:
[OPT P*3+4
.Ins
CPX #SerInID:BNE InsertCall:\   Not serial input
TAY:BNE InsertCall:\            Not a null
JSR InsertCall:BCC InsertCall:\ Put two nulls in
RTS:\                           Quit if buffer full
.InsertCall
JMP &FFFF
:
.go%
LDA #0:LDX #1:JSR &FFF4:\        What OS?
PHP:SEI:CPX #5:BNE NotCompact:\  Only needs fixing on MOS 5.00
:
LDA INSV:STA InsertCall+1:LDA INSV+1:STA InsertCall+2
LDA #Ins AND 255:STA INSV:LDA #Ins DIV 256:STA INSV+1
:
.NotCompact
PLP:RTS:EQUS Ver$
]:NEXT
PRINT"*Save SerFix ";~mcode%;" ";~O%;" "~go%OR&FFFF0000;" ";~start%