errorhandler

.PAG 'ERROR HANDLER'
;***************************************
;* STOP -- CHECK STOP KEY FLAG AND     *
;* RETURN Z FLAG SET IF FLAG TRUE.     *
;* ALSO CLOSES ACTIVE CHANNELS AND     *
;* FLUSHES KEYBOARD QUEUE.             *
;* ALSO RETURNS KEY DOWNS FROM LAST    *
;* KEYBOARD ROW IN .A.                 *
;***************************************
NSTOP	LDA STKEY       ;VALUE OF LAST ROW
	CMP #$7F        ;CHECK STOP KEY POSITION
	BNE STOP2       ;NOT DOWN
	PHP
	JSR CLRCH       ;CLEAR CHANNELS
	STA NDX         ;FLUSH QUEUE
	PLP
STOP2	RTS
.SKI 5
;************************************
;*                                  *
;* ERROR HANDLER                    *
;*                                  *
;* PRINTS KERNAL ERROR MESSAGE IF   *
;* BIT 6 OF MSGFLG SET.  RETURNS    *
;* WITH ERROR # IN .A AND CARRY.    *
;*                                  *
;************************************
;
ERROR1	LDA #1          ;TOO MANY FILES
	.BYT $2C
ERROR2	LDA #2          ;FILE OPEN
	.BYT $2C
ERROR3	LDA #3          ;FILE NOT OPEN
	.BYT $2C
ERROR4	LDA #4          ;FILE NOT FOUND
	.BYT $2C
ERROR5	LDA #5          ;DEVICE NOT PRESENT
	.BYT $2C
ERROR6	LDA #6          ;NOT INPUT FILE
	.BYT $2C
ERROR7	LDA #7          ;NOT OUTPUT FILE
	.BYT $2C
ERROR8	LDA #8          ;MISSING FILE NAME
	.BYT $2C
ERROR9	LDA #9          ;BAD DEVICE #
;
	PHA             ;ERROR NUMBER ON STACK
	JSR CLRCH       ;RESTORE I/O CHANNELS
;
	LDY #MS1-MS1
	BIT MSGFLG      ;ARE WE PRINTING ERROR?
	BVC EREXIT      ;NO...
;
	JSR MSG         ;PRINT "CBM I/O ERROR #"
	PLA
	PHA
	ORA #$30        ;MAKE ERROR # ASCII
	JSR BSOUT       ;PRINT IT
;
EREXIT	PLA
	SEC
	RTS
.END