	;**************************************************
	;*	This file contains the port addresses of  *
	;*	all I/O registers, the memory devices 	  *
	;*	start locations, the RAM length and some  *
	;*	miscellaneous constants.		  *
	;**************************************************
	;
	;
	;
	;	*******************************
	;	  NSC831 PIO REGISTER ADDRESSES
	;	*******************************
	;
	PIOA:	EQU 80H			;Data Registers
	PIOB:	EQU 81H
	PIOC: 	EQU 82H
	;
	PIODDRA:EQU 84H			;Data Direction Registers
	PIODDRB:EQU 85H
	PIODDRC:EQU 86H
	;
	PIOMDR:	EQU 87H			;Mode Definition Register
	;
	PIOAC:	EQU 88H			;Port bit-clear
	PIOBC:	EQU 89H
	PIOCC:	EQU 8AH
	;
	PIOAS:	EQU 8CH			;Port bit-set
	PIOBS:	EQU 8DH
	PIOCS:	EQU 8EH
	;
	;
	;	**********************************
	;	      DMA REGISTER ADDRESSES
	;	**********************************
	;
	DMAADD:	EQU 20H			;W/O Base & Current Address
	DMARCA:	EQU 20H			;R/O Current Address
	;
	DMACNT:	EQU 21H			;W/O Base & Current Word Count
	DMARWC:	EQU 21H			;R/O Current Word Count
	;
	DMAMOD:	EQU 2BH			;W/O Mode register
	;
	DMAMCL:	EQU 2DH			;W/O Master Clear register
	;
	DMAMSK:	EQU 2FH			;W/O Mask register (all masks)
	;
	;
	;	***********************************
	;	      EASI REGISTER ADDRESSES
	;	***********************************
	;
	EASIODR:EQU 00			;W/O Output Data Register
	EASICSD:EQU 00			;R/O Current SCSI Data
	;
	EASIICR:EQU 01			;R/W Initiator Command Register
	;
	EASIMR2:EQU 02			;R/W Mode Register 2
	;
	EASITCR:EQU 03			;R/W Target Command Register
	;
	EASISER:EQU 04			;W/O Select Enable Register
	EASICSB:EQU 04			;R/O Current SCSI Bus Status
	;
	EASISDS:EQU 05			;W/O Start DMA Send
	EASIBSR:EQU 05			;R/O Bus & Status Register
	;
	EASISDT:EQU 06			;W/O Start DMA Target Rx
	EASIIDR:EQU 06			;R/O Input Data Register
	;
	EASISDI:EQU 07			;W/O Start DMA Initiator Rx
	EASIRPI:EQU 07			;R/O Reset Parity & Interrupt  Latches
	EASIEMR:EQU 07			;R/W Enhanced Mode Register
	EASIIMR:EQU 07			;W/O Interrupt Mask Register
	EASIISR:EQU 07			;R/O Interupt Status Register
	;
	;
	;
	;	********************
	;	  MEMORY ADDRESSES
	;	********************
	;
	ROMSTT:	EQU 00			;ROM Starting Address
	RAMSTT:	EQU 8000H		;RAM Starting Address
	RAMLEN:	EQU 8000H		;Number of RAM locations
	;
	;
	;	*****************
	;	  MISCELLANEOUS
	;	*****************
	;
	STKDATA:EQU 00			;Initial stack value
	DELVAL:	EQU 24038		;2.5MHz=24038, 4MHz =38641, 
	;				;for delay counter
	INTMSK:	EQU 0BBH		;CPU Mask register address
