A2osX/DRV/SSC.I.DRV.S.txt

PR#3
PREFIX /A2OSX.BUILD
LOMEM $A00
INC 1
AUTO 6
				.LIST OFF	
				.OP	65C02
				.OR $2000
				.TF /A2OSX.BUILD/DRV/SSC.I.DRV
*--------------------------------------
				.INB /A2OSX.BUILD/INC/MACROS.I
				.INB /A2OSX.BUILD/INC/A2OSX.I
				.INB /A2OSX.BUILD/INC/MLI.ERR.I
				.INB /A2OSX.BUILD/INC/COM.6551.I
*--------------------------------------
BUF.SIZE		.EQ $40
BUF.MASK		.EQ $3F
*--------------------------------------
ZPTmpPtr1		.EQ ZPDRV
*--------------------------------------
*			File Header (16 Bytes)
*--------------------------------------
CS.START		cld
				jmp Dev.Detect			cld,jmp abs=DRV
				.DA #$61				6502,Level 1 (65c02)
				.DA #1					DRV Layout Version 1
				.DA 0
				.DA CS.END-CS.START			Code Length
				.DA DEV.HEADER-CS.START		Device Header Offset
				.DA DRV.CS.START-CS.START	Driver Code Offset
				.DA DRV.CS.END-DRV.CS.START	Drv Code Length
*--------------------------------------
* Relocation Table
*--------------------------------------
L.MSG.DETECT	.DA MSG.DETECT
L.MSG.DETECT.OK	.DA MSG.DETECT.OK
L.MSG.DETECT.KO	.DA MSG.DETECT.KO
L.DEV.HEADER.NAME	.DA DEV.HEADER.NAME
				.DA 0					End Of Reloc Table
*--------------------------------------
Dev.Detect		>STYA ARGS

				>LDYA L.MSG.DETECT
				>SYSCALL PrintF.YA
				
				stz ZPTmpPtr1
				lda #$C1
				sta ZPTmpPtr1+1
				
.1				and #$0f
				tay
				lda A2osX.S,y
				bne .3

				ldx #DEVSIG.Length-1

.2				ldy DEVSIG.Offset,x
				lda (ZPTmpPtr1),y
				cmp DEVSIG.Value,x
				bne .3
				dex
				bpl .2
				bra .4
				
.3				inc ZPTmpPtr1+1			no match, try next slot....
				lda ZPTmpPtr1+1
				cmp #$C8
				bne .1	
				
				>LDYA L.MSG.DETECT.KO
				>SYSCALL PrintF.YA

				lda #MLI.E.NODEV		Not Found in any slot, exiting
				sec
				rts	

.4				lda ZPTmpPtr1+1
				and #$0F
				pha
				tay
				lda #A2osX.S.COM
				sta A2osX.S,y
				pla
				ora #$30
				sta DEV.HEADER.NAME+3
				asl
				asl
				asl
				asl
				sta DEVSLOTn0

				>PUSHW L.DEV.HEADER.NAME
				>LDYA L.MSG.DETECT.OK
				>SYSCALL PrintF.YA
				clc
				rts
*--------------------------------------
CS.END
DEVSIG.Offset	.HS 05070B0C
DEVSIG.Value	.HS 38180131
DEVSIG.Length	.EQ DEVSIG.Value-DEVSIG.Offset
MSG.DETECT		>CSTR "Apple SSC (Super Serial Card,//c Serial Port) Driver (IRQ Enabled).\r\n"
MSG.DETECT.OK	>CSTR "SSC Installed As Device : %s\r\n"
MSG.DETECT.KO	>CSTR "No SSC Found.\r\n"
ARGS			.BS 2
*--------------------------------------
*			Device Header (16 Bytes)
*--------------------------------------
DEV.HEADER		cld
				jmp (DRV.CS.START,x)
				.DA #S.DEV.S.WRITE+S.DEV.S.READ+S.DEV.S.IRQ
				.BS 6
DEV.HEADER.NAME	>CSTR "COM1"			NAME
*--------------------------------------
*			Driver Code
*--------------------------------------
DRV.CS.START	.DA STATUS
				.DA A2osX.BADCALL
				.DA A2osX.BADCALL
				.DA A2osX.BADCALL
				.DA CONTROL
				.DA A2osX.BADCALL
				.DA OPEN
				.DA CLOSE
				.DA READ
				.DA WRITE
				.DA IRQ
L.STAT			.DA STAT
				.DA 0					end or relocation
*--------------------------------------
STATUS			>LDYA L.STAT
				clc
				rts
*--------------------------------------
CONTROL			clc
				rts
*--------------------------------------
OPEN			php
				sei
				ldx DEVSLOTn0
				
				stz SSC.RESET,x 
				
				stz INBUF.HEAD
				stz INBUF.TAIL
				stz OUTBUF.HEAD
				stz OUTBUF.TAIL
			
				lda #SSC.CTL.CLKEXT+SSC.CTL.B9600+SSC.CTL.8D+SSC.CTL.1S+SSC.CMD.NOP
				sta SSC.CTL,x
				
				lda #SSC.CMD.TEIRQ+SSC.CMD.TE+SSC.CMD.DTR
				sta SSC.CMD,x
				
				lda SSC.DATA,x		discard any garbage byte
				lda SSC.STATUS,x	clear any IRQ pending

				plp
				clc
				rts
*--------------------------------------
CLOSE			php
				sei
				ldx DEVSLOTn0
				stz SSC.RESET,x 
				plp
				clc
				rts
*--------------------------------------
READ			php
				sei
				ldx INBUF.TAIL
				cpx INBUF.HEAD
				beq .9
				
				lda INBUF,x
				inx
				cpx #BUF.SIZE
				bne .1
				
				ldx #0
				
.1				stx INBUF.TAIL
				
				plp
				clc
				rts
				
.9				plp
				lda #0
				sec
				rts
*--------------------------------------
WRITE			php
				sei
				tay						save char in Y

				ldx DEVSLOTn0

*				lda SSC.STATUS,x
*				bit #SSC.STATUS.DCD+SSC.STATUS.DSR		true when 0
*				bne .9
				
				lda OUTBUF.HEAD
				cmp OUTBUF.TAIL			Buffer Empty?
				bne .11					not empty, queue char

				lda SSC.STATUS,x
				
				and #SSC.STATUS.TDRE 	Register Empty ?
				beq .10					not empty, queue char
				
				tya						yes, write directly to ACIA
				sta SSC.DATA,x
				
				plp
				clc
				rts
	
.10				lda OUTBUF.HEAD
				
.11				tax
				inc
				and #BUF.MASK
				cmp OUTBUF.TAIL	
				beq .9					Buffer Full!!

				sta OUTBUF.TAIL
				
				tya
				sta OUTBUF,x
				
*				ldx DEVSLOTn0
*				lda #SSC.CMD.TEIRQ+SSC.CMD.DTR
*				sta SSC.CMD,x
				plp
				clc
				rts
				
.9				plp
				sec
				rts
*--------------------------------------
* IRQ Handler
* on exit, CC if handled
*--------------------------------------
IRQ				stz .8+1

.1				ldx DEVSLOTn0
				lda SSC.STATUS,x
				
*				bpl .9					IRQ from this device ? no, exit !!!!Applewin bug #308!!!!

				bit #SSC.STATUS.RDRF	incoming char?
				beq .4					

*------------ IRQ In

				ldy SSC.DATA,x			read data to clear IRQ

				ldx INBUF.HEAD
				txa
				inc
				and #BUF.MASK
				cmp INBUF.TAIL				
				beq .8					buffer full, discard and exit
				
				sta INBUF.HEAD
				tya
				sta INBUF,x

				lda #$ff
				sta	.8+1
				
				bra .1
				
*------------ IRQ Out

.3				ldx DEVSLOTn0
				lda SSC.STATUS,x
				
.4				bit #SSC.STATUS.TDRE
				beq .8					no transmition possible....

				ldy OUTBUF.TAIL			something to transmit ?
				cpy OUTBUF.HEAD
				beq .8
				
				lda OUTBUF,y
				sta SSC.DATA,x
				
				iny
				cpy #BUF.SIZE
				bne .5
				ldy #0
				
.5				sty OUTBUF.TAIL	
				
				lda #$ff
				sta	.8+1
				
				bra .3

.8				lda #$ff				did we finally handle and IRQ condtion ?
				beq .9
				clc
				rts
				
.9				sec
				rts
*--------------------------------------
DRV.CS.END
DEVSLOTn0		.BS 1
INBUF.TAIL		.BS 1
INBUF.HEAD		.BS 1
OUTBUF.TAIL		.BS 1
OUTBUF.HEAD		.BS 1
INBUF			.BS BUF.SIZE
OUTBUF			.BS BUF.SIZE
*--------------------------------------
STAT			.DA #S.DSTAT.S.WRITE+S.DSTAT.S.READ+S.DEV.S.IRQ
				.DA #0,#0,#0
				>PSTR "Serial Card/Port"
				.DA #S.DSTAT.T.CHAR
				.DA #0
				.DA $0900
*--------------------------------------
MAN
SAVE /A2OSX.SRC/DRV/SSC.I.DRV.S
ASM