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CPM OPERATING SYSTEMS/CPM 2.X/CPM 2.2/PATCHES/XMAC.ASM

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+;
+;XMAC --
+;  MACRO ASSEMBLER "MAC" CHANGES TO DISABLE 8080 OPCODES FOR CROSS-ASSEMBLY
+;    WORK
+;  THIS PATCH WAS ORIGINALLY SUPPLIED WITH MY MAC MANUAL -- RLC
+;  THIS IS TO BE PATCHED INTO MAC USING DDT.  AFTER THE PATCH IS COMPLETE,
+;    PERFORM A "SAVE 46 XMAC.COM" TO CREATE XMAC.COM.
+;
+ 
+RT	EQU	25	; 8080 REGISTER NAME
+PT	EQU	26	; PSEUDO OPCODE TYPE
+TAREA	EQU	2561H	; FREE AREA IN TOKEN MODULE
+ 
+;
+	ORG	2444H	; OVERLAY INXH - MOV B,M - RET
+	JMP	TAREA
+ 
+;
+	ORG	TAREA
+ 
+;  TYPE IS IN THE ACCUMULATOR
+	CPI	RT	; BELOW RT IF ARITHMETIC OPERATOR
+	JC	TYPEOK
+	CPI	PT	; PSEUDO OP?
+	RNZ		; RETURN WITH NON-ZERO FLAG
+ 
+;  OTHERWISE, PSEUDO-OP OR ARITHMETIC OP
+TYPEOK:
+	INX	H
+	MOV	B,M
+	CMP	A	; SET ZERO FLAG
+	RET
+ 
+	END