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CONTRIBUTIONS/cpm-handbook/cpmsrc/FIG5-4.ASM

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+; Figure 5-4
+;
+;	Useful subroutines using the Write Console Byte
+;	BDOS Function.
+;
+;	MSGOUTI (Message Out In-line)
+;	Output null-byte terminated message that follows the
+;	CALL to MSGOUTI.
+;
+;	Calling sequence
+;
+;		CALL	MSGOUTI
+;		DB	'Message',0
+;		... next instruction
+;
+;	Exit Parameters
+;		HL -> instruction following message
+;
+B$CONOUT	EQU	2	;Write console byte
+BDOS		EQU	5	;BDOS Entry Point
+;
+MSGOUTI:
+	POP	H	;HL -> Message
+	MOV	A,M	;Get next data byte
+	INX	H	;Update message pointer
+	ORA	A	;Check if null byte
+	JNZ	MSGOUTIC	;No, continue
+	PCHL		;Yes, return to next instruction
+			;after in-line message
+MSGOUTIC:
+	PUSH	H	;Save message pointer
+	MOV	E,A	;Ready for BDOS
+	MVI	C,B$CONOUT	;Function code
+	CALL	BDOS
+	JMP	MSGOUTI	;Go back for next char.
+
+