;===========================================================================
; File:	PCSERIAL.INC
; Project: MUNGA
; Contents: PC serial interface equates (TASM)
;---------------------------------------------------------------------------
;   Date    Who  Modification
; --------  ---  -----------------------------------------------------------
; 01/04/95  CPB  Initial coding
;---------------------------------------------------------------------------
; Copyright (C) 1994, Virtual World Entertainment, Inc.
; All Rights reserved worldwide
; This unpublished sourcecode is PROPRIETARY and CONFIDENTIAL
;===========================================================================

;
; UART register definitions
;
; --- LSR bit low
UART_DATA		EQU	0				;Transmitter holding/receiver data register
UART_IER			EQU	1				;Interrupt enable register
; --- LSR bit high
UART_BRDL		EQU	0				;Low byte, data rate divisor
UART_BRDH		EQU	1				;High byte, data rate divisor
; --- LSR bit "don't care"
UART_IIR			EQU	2				;Interrupt identification register
UART_LCR			EQU	3				;Line control register
UART_MCR			EQU	4				;Modem control register
UART_LSR			EQU	5				;Line status register
UART_MSR			EQU	6				;Modem status register

UART_COM1_BASE	EQU	03F8h			;COM1 port address
UART_COM2_BASE	EQU	02F8h			;COM2 port address
UART_COM3_BASE	EQU	03E8h			;COM3 port address
UART_COM4_BASE	EQU	02E8h			;COM4 port address

UART_300BAUD	EQU	0180h			;Data rate definitions
UART_1200BAUD	EQU	0060h
UART_2400BAUD	EQU	0030h
UART_9600BAUD	EQU	000Ch
UART_19KBAUD	EQU	0006h			;19,200 Baud
UART_38KBAUD	EQU	0003h			;38,400 Baud
UART_115KBAUD	EQU	0001h			;115,200 Baud

UART_IER_RDR	EQU	00000001b	;IER:receiver data available
UART_IER_THR	EQU	00000010b	;IER:transmit hold register empty
UART_IER_LSR	EQU	00000100b	;IER:data error or receipt of break
UART_IER_MSR	EQU	00001000b	;IER:MSR has changed

UART_IER_RX		EQU	00001101b	;IER:all internal receiver sources
UART_IER_ALL	EQU	00001111b	;IER:all internal sources

UART_IIR_DONE	EQU	00000001b	;IIR:zero if interrupt pending

UART_IIR_MSR	EQU	00000000b	;IIR:MSR has changed
UART_IIR_THR	EQU	00000010b	;IIR:THR is empty
UART_IIR_RDR	EQU	00000100b	;IIR:data available in RDR
UART_IIR_LSR	EQU	00000110b	;IIR:data error or receipt of break

UART_LCR_5		EQU	00000000b	;LCR:5 data bits
UART_LCR_6		EQU	00000001b	;LCR:6 data bits
UART_LCR_7		EQU	00000010b	;LCR:7 data bits
UART_LCR_8		EQU	00000011b	;LCR:8 data bits

UART_LCR_S1		EQU	00000000b	;LCR:one stop bit
UART_LCR_S2		EQU	00000100b	;LCR:1.5 stop for 5 bits, else 2 stop bits

UART_LCR_NP		EQU	00000000b	;LCR:no parity
UART_LCR_OP		EQU	00001000b	;LCR:odd parity
UART_LCR_EP		EQU	00011000b	;LCR:even parity
UART_LCR_MP		EQU	00101000b	;LCR:mark parity? (always set)
UART_LCR_SP		EQU	00111000b	;LCR:space parity? (always clear)

UART_LCR_BRK	EQU	01000000b	;LCR:transmit break

UART_LCR_ALT	EQU	10000000b	;LCR:allows access to data rate registers

UART_MCR_DTR	EQU	00000001b	;MCR:activate DTR output
UART_MCR_RTS	EQU	00000010b	;MCR:activate RTS output
UART_MCR_USR	EQU	00000100b	;MCR:activate user output line #1
UART_MCR_IRQ	EQU	00001000b	;MCR:enable interrupts (user output line #2)
UART_MCR_LBT	EQU	00010000b	;MCR:enable loopback testing

UART_LSR_RDR	EQU	00000001b	;LSR:data available in RDR
UART_LSR_OE		EQU	00000010b	;LSR:overrun error
UART_LSR_PE		EQU	00000100b	;LSR:parity error
UART_LSR_FE		EQU	00001000b	;LSR:framing error
UART_LSR_BRK	EQU	00010000b	;LSR:break detect
UART_LSR_THR	EQU	00100000b	;LSR:THR is empty
UART_LSR_TSR	EQU	01000000b	;LSR:TSR is empty
UART_LSR_ERRS	EQU	UART_LSR_OE+UART_LSR_PE+UART_LSR_FE+UART_LSR_BRK

UART_MSR_DCTS	EQU	00000001b	;MSR:delta CTS (CTS has changed)
UART_MSR_DDSR	EQU	00000010b	;MSR:delta DSR	(DSR has changed)
UART_MSR_DRI	EQU	00000100b	;MSR:delta RI  (RI has changed)
UART_MSR_DDCD	EQU	00001000b	;MSR:delta DCD (DCD has changed)
UART_MSR_CTS	EQU	00010000b	;MSR:CTS status
UART_MSR_DSR	EQU	00100000b	;MSR:DSR status
UART_MSR_RI		EQU	01000000b	;MSR:RI status
UART_MSR_DCD	EQU	10000000b	;MSR:DCD status

;-------------------------------------------------------------------------
; ASSERT_MCR macro - asserts ("turns on") selected MCR bits
;-------------------------------------------------------------------------
; Enter:
;		DX        = base port address for UART
;     theseBits = MCR bits to assert (see UART_MCR_... definitions, above)
;-------------------------------------------------------------------------
; Returns:
;		(nothing)
;-------------------------------------------------------------------------
ASSERT_MCR MACRO theseBits
	add	dx,UART_MCR				;move to MCR register
	in		al,dx						;get contents
	or		al,theseBits			;turn on bit(s)
	out	dx,al
	sub	dx,UART_MCR				;restore dx
ENDM

;-------------------------------------------------------------------------
; RETRACT_MCR macro - retracts ("turns off") selected MCR bits
;-------------------------------------------------------------------------
; Enter:
;		DX        = base port address for UART
;     theseBits = MCR bits to assert (see UART_MCR_... definitions, above)
;-------------------------------------------------------------------------
; Returns:
;		(nothing)
;-------------------------------------------------------------------------
RETRACT_MCR MACRO theseBits
	add	dx,UART_MCR				;move to MCR register
	in		al,dx						;get contents
	and	al,NOT (theseBits)	;turn off bit(s)
	out	dx,al
	sub	dx,UART_MCR				;restore dx
ENDM

;-------------------------------------------------------------------------
; ASSERT_IER macro - asserts ("turns on") selected IER bits
;-------------------------------------------------------------------------
; Enter:
;		DX        = base port address for UART
;     theseBits = MCR bits to assert (see UART_IER_... definitions, above)
;-------------------------------------------------------------------------
; Returns:
;		(nothing)
;-------------------------------------------------------------------------
ASSERT_IER MACRO theseBits
	add	dx,UART_IER				;move to IER register
	in		al,dx						;get contents
	or		al,theseBits			;turn on bit(s)
	out	dx,al
	sub	dx,UART_IER				;restore dx
ENDM

;-------------------------------------------------------------------------
; RETRACT_IER macro - retracts ("turns off") selected IER bits
;-------------------------------------------------------------------------
; Enter:
;		DX        = base port address for UART
;     theseBits = MCR bits to assert (see UART_IER_... definitions, above)
;-------------------------------------------------------------------------
; Returns:
;		(nothing)
;-------------------------------------------------------------------------
RETRACT_IER MACRO theseBits
	add	dx,UART_IER				;move to IER register
	in		al,dx						;get contents
	and	al,NOT (theseBits)	;turn off bit(s)
	out	dx,al
	sub	dx,UART_IER				;restore dx
ENDM

;-------------------------------------------------------------------------
; ASSERT_IIR macro - asserts ("turns on") selected IIR bits
;-------------------------------------------------------------------------
; Enter:
;		DX        = base port address for UART
;     theseBits = MCR bits to assert (see UART_IIR_... definitions, above)
;-------------------------------------------------------------------------
; Returns:
;		(nothing)
;-------------------------------------------------------------------------
ASSERT_IIR MACRO theseBits
	add	dx,UART_IIR				;move to IIR register
	in		al,dx						;get contents
	or		al,theseBits			;turn on bit(s)
	out	dx,al
	sub	dx,UART_IIR				;restore dx
ENDM

;-------------------------------------------------------------------------
; RETRACT_IIR macro - retracts ("turns off") selected IIR bits
;-------------------------------------------------------------------------
; Enter:
;		DX        = base port address for UART
;     theseBits = MCR bits to assert (see UART_IIR_... definitions, above)
;-------------------------------------------------------------------------
; Returns:
;		(nothing)
;-------------------------------------------------------------------------
RETRACT_IIR MACRO theseBits
	add	dx,UART_IIR				;move to IIR register
	in		al,dx						;get contents
	and	al,NOT (theseBits)	;turn off bit(s)
	out	dx,al
	sub	dx,UART_IIR				;restore dx
ENDM

;-------------------------------------------------------------------------
; SETFORMAT_AL macro - sets LCR from al
;-------------------------------------------------------------------------
; Enter:
;		DX = base port address for UART
;     AL = LCR bits to set (see UART_LCR... definitions, above)
;-------------------------------------------------------------------------
; Returns:
;		(nothing)
;-------------------------------------------------------------------------
SETFORMAT_AL MACRO
	add	dx,UART_LCR				;move to UART_LCR
	out	dx,al
	sub	dx,UART_LCR				;restore base address
ENDM

;-------------------------------------------------------------------------
; SETBAUD_CX macro - sets data rate
;-------------------------------------------------------------------------
; Enter:
;		DX = base port address for UART
;		CX = data rate value
;-------------------------------------------------------------------------
; Returns:
;		(nothing)
;-------------------------------------------------------------------------
; Side effects:
;     Modifies AL
;-------------------------------------------------------------------------
SETBAUD_CX MACRO
			;---------------------------------
			; Select baud rate division registers
			;---------------------------------
			add	dx,UART_LCR						;turn on UART_LCR_ALT
			in		al,dx
			or		al,UART_LCR_ALT
			out	dx,al
			sub	dx,UART_LCR						;restore base address
			;---------------------------------
			; Set baud rate division registers
			;---------------------------------
			mov	al,cl								;get low divisor in al
			out	dx,al								;write to BRDL
			inc	dx									;move to high divisor address
			mov	al,ch								;get high divisor in al
			out	dx,al								;write to BRDH
			dec	dx									;restore base address
			;---------------------------------
			; Deselect baud rate division registers
			;---------------------------------
			add	dx,UART_LCR						;turn off UART_LCR_ALT
			in		al,dx
			and	al,NOT UART_LCR_ALT
			out	dx,al
			sub	dx,UART_LCR						;restore base address
ENDM

;end of PCSERIAL.INC