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Old 2nd Nov 2019, 11:15 pm   #261
john_newcombe
Hexode
 
Join Date: Apr 2019
Location: Skipton, North Yorkshire, UK.
Posts: 252
Default Re: Gemini 80-Bus System

Ok, but just so I am clear, when should I do this? before or after the select?

Code:
	.Z80
	ASEG
	ORG 0100H
	.PHASE 0100H

.1797	EQU	0E0H		;Base address
WCTRL	EQU	.1797+5		;SASI (Winchester) control/status port
WDATA	EQU	.1797+6		;SASI (Winchester) Data port

TEST:

	LD	A,0FEh		; set Data 0 here ???
	OUT	(WDATA),A	; 

	LD	A,5
	OUT	(WCTRL),A	; set the -SEL
	IN	A,(WCTRL)	; read status
	JR	TEST		; loop
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