Initial commit.

atari/bugger.src

@@ -0,0 +1,124 @@
+	PAGE
+	SBTTL "--- DEBUGGER: CBM64 ---"
+
+	; --------------
+	; CBM64 DEBUGGER
+	; --------------
+
+	; ENTRY: BREAKPOINT ID IN [A]
+
+BLINE:	DB	"B:    OP:   PC:       B:   S:   V:"
+BLINL	EQU	$-BLINE
+
+BUGLIN	EQU	SCREEN+40
+
+DOBUG:	LDX	CONSOL		; CHECK CONSOLE
+	CPX	#5		; "SELECT" PRESSED?
+	BNE	BUGIT		; IF SO,
+	RTS			; EXIT
+
+BUGIT:	PHA			; ELSE SAVE BREAK ID
+
+	LDX	#39
+DBG0:	LDA	#0
+	STA	BUGLIN,X	; CLEAR SCREEN LINE
+	DEX
+	BPL	DBG0
+
+	LDX	#0
+DBG1:	LDA	BLINE,X		; PRINT DEBUGGER TEXT
+	STA	BUGLIN,X
+	INX
+	CPX	#BLINL
+	BCC	DBG1
+
+	LDX	#2		; INIT "CURSOR"
+	PLA
+	JSR	HEX		; SHOW BREAKPOINT
+
+	LDA 	OPCODE
+	BMI	ITQ0
+	LDA	#'2'
+	BNE	SHOWOP
+
+ITQ0:	CMP	#$B0
+	BCS	ITQ1
+	LDA	#'1'
+	BNE	SHOWOP
+
+ITQ1:	CMP	#$C0
+	BCS	ITQ2
+	LDA	#'0'
+	BNE	SHOWOP
+
+ITQ2:	CMP	#$E0
+	BCS	ITQ3
+	LDA	#'E'
+	BNE	SHOWOP
+
+ITQ3:	LDA	#'X'
+
+SHOWOP:	LDX	#5		; SET CURSOR
+	STA	BUGLIN,X
+
+	LDX	#9		; CURSOR FOR OP ID
+	LDA	OPCODE
+	JSR	HEX
+
+	LDX	#15		; CURSOR FOR PC
+	LDA	ZPCH
+	JSR	HEX
+	LDA	ZPCM
+	JSR	HEX
+	LDA	ZPCL
+	JSR	HEX
+
+	LDX	#24		; CURSOR FOR BYTE
+	LDA	MBYTE
+	JSR	HEX
+
+	LDX	#29		; CURSOR FOR [ZSP]
+	LDA	ZSP
+	JSR	HEX
+
+	LDX	#34		; CURSOR FOR [MPC]
+	LDA	MPCH
+	JSR	HEX
+	LDA	MPCM
+	JSR	HEX
+	LDA	MPCL
+	JSR	HEX
+
+	LDA	CONSOL
+	CMP	#6		; "START" PRESSED?
+	BNE	LETEX		; EXIT IF NOT
+
+LETGO:	LDA	CONSOL		; ELSE WAIT FOR
+	CMP	#6		; "START" TO BE RELEASED
+	BEQ	LETGO
+
+LETEX:	RTS
+
+	; CONVERT [A] TO HEX & PRINT
+
+HEX:	PHA
+	LSR	A
+	LSR	A
+	LSR	A
+	LSR	A
+	JSR	NIB
+	PLA
+
+NIB:	AND	#%00001111
+	TAY
+	LDA	HCHARS,Y
+	STA	BUGLIN,X
+	INX
+	RTS
+
+HCHARS:	DB	"0123456789ABCDEF"
+
+MBYTE:	DB	0
+
+	END
+