mv cbm510/crt0.o cbm510.o
cp cbm510/*.emd .
cp cbm510/*.joy .
+ cp cbm510/cbm510-stdser.ser cbm510-std.ser
#-----------------------------------------------------------------------------
# PET-II series
%.joy: %.o ../runtime/zeropage.o extzp.o
@$(LD) -t module -o $@ $^
+%.ser: %.o ../runtime/zeropage.o extzp.o
+ @$(LD) -t module -o $@ $^
+
%.tgi: %.o ../runtime/zeropage.o extzp.o
@$(LD) -t module -o $@ $^
pokesys.o \
randomize.o \
revers.o \
- rs232.o \
sysuname.o \
tgi_mode_table.o
JOYS = cbm510-stdjoy.joy
+SERS = cbm510-stdser.ser
+
TGIS =
#--------------------------------------------------------------------------
.PHONY: all clean zap
-all: $(OBJS) $(EMDS) $(JOYS) $(TGIS)
+all: $(OBJS) $(EMDS) $(JOYS) $(SERS) $(TGIS)
../runtime/zeropage.o:
$(MAKE) -C $(dir $@) $(notdir $@)
clean:
- @$(RM) $(OBJS) $(EMDS:.emd=.o) $(JOYS:.joy=.o) $(TGIS:.tgi=.o)
+ @$(RM) $(OBJS) $(EMDS:.emd=.o) $(JOYS:.joy=.o) $(SERS:.ser=.o) $(TGIS:.tgi=.o)
zap: clean
- @$(RM) $(EMDS) $(JOYS) $(TGIS)
+ @$(RM) $(EMDS) $(JOYS) $(SERS) $(TGIS)
; Get the direction bits
- ldy #CIA_PRB
+ ldy #CIA::PRB
lda (cia2),y ; Read joystick inputs
sta tmp1
; Get the fire bits
- ldy #CIA_PRA
+ ldy #CIA::PRA
lda (cia2),y
; Make the result value
--- /dev/null
+;
+; Serial driver for the builtin 6551 ACIA of the Commodore 510.
+;
+; Ullrich von Bassewitz, 2003-12-18
+;
+; The driver is based on the cc65 rs232 module, which in turn is based on
+; Craig Bruce device driver for the Switftlink/Turbo-232.
+;
+; SwiftLink/Turbo-232 v0.90 device driver, by Craig Bruce, 14-Apr-1998.
+;
+; This software is Public Domain. It is in Buddy assembler format.
+;
+; This device driver uses the SwiftLink RS-232 Serial Cartridge, available from
+; Creative Micro Designs, Inc, and also supports the extensions of the Turbo232
+; Serial Cartridge. Both devices are based on the 6551 ACIA chip. It also
+; supports the "hacked" SwiftLink with a 1.8432 MHz crystal.
+;
+; The code assumes that the kernal + I/O are in context. On the C128, call
+; it from Bank 15. On the C64, don't flip out the Kernal unless a suitable
+; NMI catcher is put into the RAM under then Kernal. For the SuperCPU, the
+; interrupt handling assumes that the 65816 is in 6502-emulation mode.
+;
+
+ .include "zeropage.inc"
+ .include "extzp.inc"
+ .include "ser-kernel.inc"
+ .include "ser-error.inc"
+ .include "cbm510.inc"
+
+
+; ------------------------------------------------------------------------
+; Header. Includes jump table
+
+.segment "JUMPTABLE"
+
+; Driver signature
+
+ .byte $73, $65, $72 ; "ser"
+ .byte SER_API_VERSION ; Serial API version number
+
+; Jump table.
+
+ .word INSTALL
+ .word UNINSTALL
+ .word OPEN
+ .word CLOSE
+ .word GET
+ .word PUT
+ .word STATUS
+ .word IOCTL
+ .word IRQ
+
+;----------------------------------------------------------------------------
+;
+; Global variables
+;
+
+.bss
+RecvHead: .res 1 ; Head of receive buffer
+RecvTail: .res 1 ; Tail of receive buffer
+RecvFreeCnt: .res 1 ; Number of bytes in receive buffer
+SendHead: .res 1 ; Head of send buffer
+SendTail: .res 1 ; Tail of send buffer
+SendFreeCnt: .res 1 ; Number of bytes in send buffer
+
+Stopped: .res 1 ; Flow-stopped flag
+RtsOff: .res 1 ;
+
+; Send and receive buffers: 256 bytes each
+RecvBuf: .res 256
+SendBuf: .res 256
+
+.rodata
+
+; Tables used to translate RS232 params into register values
+
+BaudTable: ; bit7 = 1 means setting is invalid
+ .byte $FF ; SER_BAUD_45_5
+ .byte $01 ; SER_BAUD_50
+ .byte $02 ; SER_BAUD_75
+ .byte $03 ; SER_BAUD_110
+ .byte $04 ; SER_BAUD_134_5
+ .byte $05 ; SER_BAUD_150
+ .byte $06 ; SER_BAUD_300
+ .byte $07 ; SER_BAUD_600
+ .byte $08 ; SER_BAUD_1200
+ .byte $09 ; SER_BAUD_1800
+ .byte $0A ; SER_BAUD_2400
+ .byte $0B ; SER_BAUD_3600
+ .byte $0C ; SER_BAUD_4800
+ .byte $0D ; SER_BAUD_7200
+ .byte $0E ; SER_BAUD_9600
+ .byte $0F ; SER_BAUD_19200
+ .byte $FF ; SER_BAUD_38400
+ .byte $FF ; SER_BAUD_57600
+ .byte $FF ; SER_BAUD_115200
+ .byte $FF ; SER_BAUD_230400
+
+BitTable:
+ .byte $60 ; SER_BITS_5
+ .byte $40 ; SER_BITS_6
+ .byte $20 ; SER_BITS_7
+ .byte $00 ; SER_BITS_8
+
+StopTable:
+ .byte $00 ; SER_STOP_1
+ .byte $80 ; SER_STOP_2
+
+ParityTable:
+ .byte $00 ; SER_PAR_NONE
+ .byte $20 ; SER_PAR_ODD
+ .byte $60 ; SER_PAR_EVEN
+ .byte $A0 ; SER_PAR_MARK
+ .byte $E0 ; SER_PAR_SPACE
+
+.code
+
+;----------------------------------------------------------------------------
+; INSTALL routine. Is called after the driver is loaded into memory. If
+; possible, check if the hardware is present.
+; Must return an SER_ERR_xx code in a/x.
+;
+; Since we don't have to manage the IRQ vector on the Plus/4, this is actually
+; the same as:
+;
+; UNINSTALL routine. Is called before the driver is removed from memory.
+; Must return an SER_ERR_xx code in a/x.
+
+
+INSTALL:
+UNINSTALL:
+
+; Deactivate DTR and disable 6551 interrupts
+
+ lda #%00001010
+ jsr write_cmd
+
+; Done, return an error code
+
+ lda #<SER_ERR_OK
+ tax ; A is zero
+ rts
+
+;----------------------------------------------------------------------------
+; PARAMS routine. A pointer to a ser_params structure is passed in ptr1.
+; Must return an SER_ERR_xx code in a/x.
+
+OPEN:
+
+; Check if the handshake setting is valid
+
+ ldy #SER_PARAMS::HANDSHAKE ; Handshake
+ lda (ptr1),y
+ cmp #SER_HS_HW ; This is all we support
+ bne InvParam
+
+; Initialize buffers
+
+ jsr InitBuffers
+
+; Set the value for the control register, which contains stop bits, word
+; length and the baud rate.
+
+ ldy #SER_PARAMS::BAUDRATE
+ lda (ptr1),y ; Baudrate index
+ tay
+ lda BaudTable,y ; Get 6551 value
+ bmi InvBaud ; Branch if rate not supported
+ sta tmp1
+
+ ldy #SER_PARAMS::DATABITS ; Databits
+ lda (ptr1),y
+ tay
+ lda BitTable,y
+ ora tmp1
+ sta tmp1
+
+ ldy #SER_PARAMS::STOPBITS ; Stopbits
+ lda (ptr1),y
+ tay
+ lda StopTable,y
+ ora tmp1
+ ora #%00010000 ; Receiver clock source = baudrate
+ ldy #ACIA::CTRL
+ jsr write
+
+; Set the value for the command register. We remember the base value in
+; RtsOff, since we will have to manipulate ACIA_CMD often.
+
+ ldy #SER_PARAMS::PARITY ; Parity
+ lda (ptr1),y
+ tay
+ lda ParityTable,y
+ ora #%00000001 ; DTR active
+ sta RtsOff
+ ora #%00001000 ; Enable receive interrupts
+ jsr write_cmd
+
+; Done
+
+ lda #<SER_ERR_OK
+ tax ; A is zero
+ rts
+
+; Invalid parameter
+
+InvParam:
+ lda #<SER_ERR_INIT_FAILED
+ ldx #>SER_ERR_INIT_FAILED
+ rts
+
+; Baud rate not available
+
+InvBaud:
+ lda #<SER_ERR_BAUD_UNAVAIL
+ ldx #>SER_ERR_BAUD_UNAVAIL
+ rts
+
+;----------------------------------------------------------------------------
+; CLOSE: Close the port, disable interrupts and flush the buffer. Called
+; without parameters. Must return an error code in a/x.
+;
+
+CLOSE:
+
+; Stop interrupts, drop DTR
+
+ lda #%00001010
+ jsr write_cmd
+
+; Initalize buffers.
+
+ jsr InitBuffers
+
+; Return OK
+
+ lda #<SER_ERR_OK
+ tax ; A is zero
+ rts
+
+;----------------------------------------------------------------------------
+; GET: Will fetch a character from the receive buffer and store it into the
+; variable pointer to by ptr1. If no data is available, SER_ERR_NO_DATA is
+; return.
+;
+
+GET: ldx SendFreeCnt ; Send data if necessary
+ inx ; X == $FF?
+ beq @L1
+ lda #$00
+ jsr TryToSend
+
+; Check for buffer empty
+
+@L1: lda RecvFreeCnt
+ cmp #$ff
+ bne @L2
+ lda #<SER_ERR_NO_DATA
+ ldx #>SER_ERR_NO_DATA
+ rts
+
+; Check for flow stopped & enough free: release flow control
+
+@L2: ldx Stopped
+ beq @L3
+ cmp #63
+ bcc @L3
+ lda #$00
+ sta Stopped
+ lda RtsOff
+ ora #%00001000
+ jsr write_cmd
+
+; Get byte from buffer
+
+@L3: ldx RecvHead
+ lda RecvBuf,x
+ inc RecvHead
+ inc RecvFreeCnt
+ ldx #$00
+ sta (ptr1,x)
+ txa ; Return code = 0
+ rts
+
+;----------------------------------------------------------------------------
+; PUT: Output character in A.
+; Must return an error code in a/x.
+;
+
+PUT:
+
+; Try to send
+
+ ldx SendFreeCnt
+ inx ; X = $ff?
+ beq @L2
+ pha
+ lda #$00
+ jsr TryToSend
+ pla
+
+; Put byte into send buffer & send
+
+@L2: ldx SendFreeCnt
+ bne @L3
+ lda #<SER_ERR_OVERFLOW ; X is already zero
+ rts
+
+@L3: ldx SendTail
+ sta SendBuf,x
+ inc SendTail
+ dec SendFreeCnt
+ lda #$ff
+ jsr TryToSend
+ lda #<SER_ERR_OK
+ tax
+ rts
+
+;----------------------------------------------------------------------------
+; STATUS: Return the status in the variable pointed to by ptr1.
+; Must return an error code in a/x.
+;
+
+STATUS: lda #$0F
+ sta IndReg
+ ldy #ACIA::STATUS
+ lda (acia),y
+ ldx #0
+ sta (ptr1,x)
+ lda IndReg
+ sta ExecReg
+ txa ; SER_ERR_OK
+ rts
+
+;----------------------------------------------------------------------------
+; IOCTL: Driver defined entry point. The wrapper will pass a pointer to ioctl
+; specific data in ptr1, and the ioctl code in A.
+; Must return an error code in a/x.
+;
+
+IOCTL: lda #<SER_ERR_INV_IOCTL ; We don't support ioclts for now
+ ldx #>SER_ERR_INV_IOCTL
+ rts
+
+;----------------------------------------------------------------------------
+; IRQ: Called from the builtin runtime IRQ handler as a subroutine. All
+; registers are already save, no parameters are passed and no return code
+; is expected.
+;
+
+IRQ: lda #$0F
+ sta IndReg ; Switch to the system bank
+ ldy #ACIA::STATUS
+ lda (acia),y ; Check ACIA status for receive interrupt
+ and #$08
+ beq @L9 ; Jump if no ACIA interrupt
+ ldy #ACIA::DATA
+ lda (acia),y ; Get byte from ACIA
+ ldx RecvFreeCnt ; Check if we have free space left
+ beq @L1 ; Jump if no space in receive buffer
+ ldy RecvTail ; Load buffer pointer
+ sta RecvBuf,y ; Store received byte in buffer
+ inc RecvTail ; Increment buffer pointer
+ dec RecvFreeCnt ; Decrement free space counter
+ cpx #33 ; Check for buffer space low
+ bcs @L9 ; Assert flow control if buffer space low
+
+; Assert flow control if buffer space too low
+
+@L1: lda RtsOff
+ ldy #ACIA::CMD
+ sta (acia),y
+ sta Stopped
+
+; Done, switch back to the execution segment
+
+@L9: lda ExecReg
+ sta IndReg
+ rts
+
+;----------------------------------------------------------------------------
+; Try to send a byte. Internal routine. A = TryHard
+
+.proc TryToSend
+
+ sta tmp1 ; Remember tryHard flag
+ lda #$0F
+ sta IndReg ; Switch to the system bank
+@L0: lda SendFreeCnt
+ cmp #$ff
+ beq @L3 ; Bail out
+
+; Check for flow stopped
+
+@L1: lda Stopped
+ bne @L3 ; Bail out
+
+; Check that swiftlink is ready to send
+
+@L2: ldy #ACIA::STATUS
+ lda (acia),y
+ and #$10
+ bne @L4
+ bit tmp1 ; Keep trying if must try hard
+ bmi @L0
+
+; Switch back the bank and return
+
+@L3: lda ExecReg
+ sta IndReg
+ rts
+
+; Send byte and try again
+
+@L4: ldx SendHead
+ lda SendBuf,x
+ ldy #ACIA::DATA
+ sta (acia),y
+ inc SendHead
+ inc SendFreeCnt
+ jmp @L0
+
+.endproc
+
+
+;----------------------------------------------------------------------------
+; Initialize buffers
+
+InitBuffers:
+ ldx #0
+ stx Stopped
+ stx RecvHead
+ stx RecvTail
+ stx SendHead
+ stx SendTail
+ dex ; X = 255
+ stx RecvFreeCnt
+ stx SendFreeCnt
+ rts
+
+;----------------------------------------------------------------------------
+; Write to the ACIA changing the indirect segment. Offset is in Y, value in A.
+
+write_cmd:
+ ldy #ACIA::CMD
+write: pha
+ lda #$0F
+ sta IndReg
+ pla
+ sta (acia),y
+ lda ExecReg
+ sta IndReg
+ rts
+
; -----------------------------------
KbdScanBuf = $20 ; Intermediate for keyboard scan
-; RS232 stuff
-RecvHead = $21 ; Head of receive buffer
-RecvTail = $22 ; Tail of receive buffer
-RecvFreeCnt = $23 ; Number of bytes in receive buffer
-SendHead = $24 ; Head of send buffer
-SendTail = $25 ; Tail of send buffer
-SendFreeCnt = $26 ; Number of bytes free in send buffer
FileNameAdrLo = $90
FileNameAdrHi = $91
FileNameAdrSeg = $92
-SaveAdrLow = $93
-SaveAdrHi = $94
-SaveAdrSeg = $95
-EndAdrLow = $96
-EndAdrHi = $97
-EndAdrSeg = $98
-StartAdrLow = $99
-StartAdrHi = $9A
-StartAdrSeg = $9B
-Status = $9C
FileNameLen = $9D
LogicalAdr = $9E
FirstAdr = $9F
SecondAdr = $A0
-DefInpDev = $A1
-DefOutDev = $A2
-TapeBufPtr = $A3
-TapeBufPtrSeg = $A5
-rs232BufPtr = $A6
-rs232BufPtrSeg = $A8
-StopKeyFlag = $A9
-CTemp = $AA
-snsw1 = $AB
-SegChgPtr = $AC
-PChighSave = $AE
-PClowSave = $AF
-SRSave = $B0
-ACSave = $B1
-XRSave = $B2
-YRSave = $B3
-SPSave = $B4
IndSegSave = $B5
-IRQSaveHi = $B7
-IRQSaveLo = $B8
-Adr1 = $B9
-Adr2 = $BB
-MoniCntr = $BD
-MoniTmp = $BE
-MoniDevNr = $BF
-PgmKeyBuf = $C0
-PgmKeyPtr = $C2
-sedsal = $C4
-sedeal = $C6
SCREEN_PTR = $C8
CURS_Y = $CA
CURS_X = $CB
PgmKeyIndex = $D6
RepeatCount = $D7
RepeatDelay = $D8
-sedt1 = $D9 ; Temp
-sedt2 = $DA ; Temp, frequently used
-PrtData = $DB
-ScreenTop = $DC
-ScreenBot = $DD
-ScreenLeft = $DE
-ScreenRight = $DF
ModKey = $E0
NorKey = $E1
-BitTable = $E2
CURS_FLAG = $E6 ; 1 = no cursor
CURS_BLINK = $E7 ; cursor blink counter
CRAM_PTR = $E8
-TempColor = $EA
CURS_STATE = $EB ; Cursor blink state
CHARCOLOR = $EC
CURS_COLOR = $ED ; Color behind cursor
-OutCharTmp = $EE
-ScreenSeq = $EF ; Segment of video RAM
;-----------------------------------------------------------------------------
; Page 3 variables
IRQVec = $0300
BRKVec = $0302
NMIVec = $0304
-openVec = $0306
-closeVec = $0308
-chkinVec = $030A
-ckoutVec = $030C
-clrchVec = $030E
-basinVec = $0310
-bsoutVec = $0312
-stopVec = $0314
-getinVec = $0316
-clallVec = $0318
-loadVec = $031A
-saveVec = $031C
-usrcmd = $031E
-escvec = $0320
-ctrlvec = $0322
-secndVec = $0324
-tksaVec = $0326
-acptrVec = $0328
-cioutVec = $032A
-untlkVec = $032C
-unlsnVec = $032E
-listnVec = $0330
-talkVec = $0332
;
;
SysMemTop = $0355
UsrMemBot = $0358
UsrMemTop = $035B
-TimOut = $035E
-VerifyFlag = $035F
DevTabIndex = $0360
-MsgFlag = $0361
-CassBufPtr = $0362
-t1 = $0363
-t2 = $0364
-XSave = $0365
-SaveX = $0366
-SaveXt = $0367
-temp = $0368
-alarm = $0369
-TapeVec = $036A
-LoadStAdr = $036F
-CassMotFlag = $0375
-m6551Ctrl = $0376
-m6551Cmd = $0377
-rs232status = $037A
-dcddsr = $037B
-rs232head = $037C
-rs232tail = $037D
PgmKeyEnd = $0380
PgmKeySeg = $0382
RVS = $0383
-linetmp = $0398
LastPrtChar = $0399
InsertFlag = $039A
ScrollFlag = $039B
-FktTemp = $039C
PgmKeyIdx = $039D
LogScrollFlag = $039E
BellMode = $039F ; Bell on/off 00 = an
SegSave = $03A0
TabStopTable = $03A1 ; 80 bits for tabstops
KeyBuf = $03AB ; Keyboard buffer
-funvec = $03B5 ; Vector for function key handline
-sedt3 = $03B9
-MoniSegSave = $03f0
-wstvec = $03F8
-WstFlag = $03FA ; Warm start flag
; ---------------------------------------------------------------------------
; Screen size
; I/O $db00: CIA 6526 Inter Process Communication
; I/O $dc00: CIA 6526
-CIA_PRA = $00
-CIA_PRB = $01
-CIA_DDRA = $02
-CIA_DDRB = $03
-CIA_ICR = $0D
-CIA_CRA = $0E
-CIA_CRB = $0F
+.struct CIA
+ PRA .byte
+ PRB .byte
+ DDRA .byte
+ DDRB .byte
+ .union
+ .struct
+ TALO .byte
+ TAHI .byte
+ .endstruct
+ TA .word
+ .endunion
+ .union
+ .struct
+ TBLO .byte
+ TBHI .byte
+ .endstruct
+ TB .word
+ .endunion
+ TOD10 .byte
+ TODSEC .byte
+ TODMIN .byte
+ TODHR .byte
+ SDR .byte
+ ICR .byte
+ CRA .byte
+ CRB .byte
+.endstruct
; I/O $dd00: ACIA 6551
-; acia = $dd00
-
- ADataReg = $00
- AStatusReg = $01
- ACmdReg = $02
- ACtrlReg = $03
-
+.struct ACIA
+ DATA .byte
+ STATUS .byte
+ CMD .byte
+ CTRL .BYTE
+.endstruct
; I/O $de00: Triport #1 6525
-
-; tpi1 = $de00
-
- tpiPortA = $00
- tpiPortB = $01
- tpiPortC = $02
- tpiIntLatch = $02
- tpiDDRA = $03
- tpiDDRB = $04
- tpiDDRC = $05
- tpiIntMask = $05
- tpiCtrlReg = $06
- tpiActIntReg = $07
-
-
-
; I/O $df00: Triport #2 6525
-; tpi2 = $df00
-
+.struct TPI
+ PRA .byte
+ PRB .byte
+ .union
+ PRC .byte
+ INT .byte
+ .endunion
+ DDRA .byte
+ DDRB .byte
+ .union
+ DDRC .byte
+ IMR .byte
+ .endunion
+ CR .byte
+ AIR .byte
+.endstruct
; Out video memory address
; CA (STATVID) = 0
; CB (VICDOTSEL) = 0
- ldy #tpiCtrlReg
+ ldy #TPI::CR
lda (tpi1),y
sta vidsave+0
and #%00001111
; Set bit 14/15 of the VIC address range to the high bits of __VIDRAM_START__
; PC6/PC7 (VICBANKSEL 0/1) = 11
- ldy #tpiPortC
+ ldy #TPI::PRC
lda (tpi2),y
sta vidsave+1
and #$3F
; Switch back the video to the system bank
- ldy #tpiCtrlReg
+ ldy #TPI::CR
lda vidsave+0
sta (tpi1),y
- ldy #tpiPortC
+ ldy #TPI::PRC
lda vidsave+1
sta (tpi2),y
; ------------------------------------------------------------------------
.globalzp vic, sid, cia1, cia2, acia, tpi1, tpi2, ktab1
- .globalzp ktab2, ktab3, ktab4, time, RecvBuf, SendBuf
+ .globalzp ktab2, ktab3, ktab4, time
ktab3: .res 2
ktab4: .res 2
time: .res 4
-RecvBuf: .res 2 ; RS232 receive buffer
-SendBuf: .res 2 ; RS232 transmit buffer
cld
lda #$0F
sta IndReg
- ldy #tpiActIntReg
+ ldy #TPI::AIR
lda (tpi1),y ; Interrupt Register 6525
beq noirq
; -------------------------------------------------------------------------
; Done
-irqend: ldy #tpiActIntReg
+irqend: ldy #TPI::AIR
sta (tpi1),y ; Clear interrupt
noirq: pla
-;
+;
; Ullrich von Bassewitz, 13.09.2001
;
; Keyboard polling stuff for the 510.
sta NorKey
lda #$00
sta KbdScanBuf
- ldy #tpiPortB
+ ldy #TPI::PRB
sta (tpi2),y
- ldy #tpiPortA
+ ldy #TPI::PRA
sta (tpi2),y
jsr Poll
and #$3F
jmp NoKey
L1: lda #$FF
- ldy #tpiPortA
+ ldy #TPI::PRA
sta (tpi2),y
asl a
- ldy #tpiPortB
+ ldy #TPI::PRB
sta (tpi2),y
jsr Poll
pha
dex
bpl L4
sec
- ldy #tpiPortB
+ ldy TPI::PRB
lda (tpi2),y
rol a
sta (tpi2),y
- ldy #tpiPortA
+ ldy #TPI::PRA
lda (tpi2),y
rol a
sta (tpi2),y
NoKey: ldy #$FF
Done: sty LastIndex
End: lda #$7F
- ldy #tpiPortA
+ ldy #TPI::PRA
sta (tpi2),y
- ldy #tpiPortB
+ ldy #TPI::PRB
lda #$FF
sta (tpi2),y
rts
; Poll the keyboard port until it's stable
.proc Poll
- ldy #tpiPortC
+ ldy TPI::PRC
L1: lda (tpi2),y
sta KeySave
lda (tpi2),y
+++ /dev/null
-;
-; SwiftLink/Turbo-232 v0.90 device driver, by Craig Bruce, 14-Apr-1998.
-;
-; This software is Public Domain. It is in Buddy assembler format.
-;
-; This device driver uses the SwiftLink RS-232 Serial Cartridge, available from
-; Creative Micro Designs, Inc, and also supports the extensions of the Turbo232
-; Serial Cartridge. Both devices are based on the 6551 ACIA chip. It also
-; supports the "hacked" SwiftLink with a 1.8432 MHz crystal.
-;
-; The code assumes that the kernal + I/O are in context. On the C128, call
-; it from Bank 15. On the C64, don't flip out the Kernal unless a suitable
-; NMI catcher is put into the RAM under then Kernal. For the SuperCPU, the
-; interrupt handling assumes that the 65816 is in 6502-emulation mode.
-;
-;--------------------------------------------------------------------------
-;
-; Adapted for the use with the cc65 runtime library by
-; Ullrich von Bassewitz (uz@musoftware.de) 02-May-1999.
-;
-; All external functions are C callable, the return value is an error code.
-;
-
-
- .importzp ptr1, ptr2, tmp1, tmp2
- .importzp acia, RecvBuf, SendBuf
- .import popa, popax
- .import sys_bank, restore_bank
- .export _rs232_init, _rs232_params, _rs232_done, _rs232_get
- .export _rs232_put, _rs232_pause, _rs232_unpause, _rs232_status
- .export k_rs232
-
- .include "cbm510.inc"
-
-
-;----------------------------------------------------------------------------
-;
-; Global variables
-;
-
-.bss
-DropCnt: .res 4 ; Number of bytes lost from rx buffer full
-Initialized: .res 1 ; Flag indicating driver is initialized
-Stopped: .res 1 ; Flow-stopped flag
-RtsOff: .res 1 ;
-Errors: .res 1 ; Number of bytes received in error, low byte
-BaudCode: .res 1 ; Current baud in effect
-
-; Segment, the RS232 buffers are in
-BufferSeg = 2
-
-; UART register offsets
-RegData = 0 ; Data register
-RegStatus = 1 ; Status register
-RegCommand = 2 ; Command register
-RegControl = 3 ; Control register
-
-; Error codes. Beware: The codes must match the codes in the C header file
-ErrNotInitialized = $01
-ErrBaudTooFast = $02
-ErrBaudNotAvail = $03
-ErrNoData = $04
-ErrOverflow = $05
-
-
-.code
-
-;----------------------------------------------------------------------------
-;
-; unsigned char __fastcall__ rs232_init (char hacked);
-; /* Initialize the serial port, install the interrupt handler. The parameter
-; * must be true (non zero) for a hacked swiftlink and false (zero) otherwise.
-; */
-;
-
-_rs232_init:
- bit Initialized ;** shut down if started
- bpl @L1
- pha
- jsr _rs232_done
- pla
-
-; Initialize buffers & control
-
-@L1: lda #0
- sta RecvHead
- sta SendHead
- sta RecvTail
- sta SendTail
- sta Errors
- sta Stopped
- lda #255
- sta RecvFreeCnt
- sta SendFreeCnt
-
-; Set default to 2400-8N1, enable interrupts
-
- jsr sys_bank ; Switch indirect to system bank
-
- ldy #RegData
- lda (acia),y
- ldy #RegStatus
- lda (acia),y
- lda #$18
- ldy #RegControl
- sta (acia),y
-
- lda #$01
- sta RtsOff
- ora #$08
- ldy #RegCommand
- sta (acia),y
- lda #$06
- sta BaudCode
-
- jsr restore_bank
-
- lda #$ff
- sta Initialized
- lda #$00
- tax
- rts
-
-;----------------------------------------------------------------------------
-;
-; unsigned char __fastcall__ rs232_params (unsigned char params, unsigned char parity);
-; /* Set the port parameters. Use a combination of the #defined values above. */
-;
-; Set communication parameters.
-;
-; baud rates stops word | parity
-; --------------------- ----- ----- | ---------
-; $00=50 $08=9600 $00=1 $00=8 | $00=none
-; $01=110 $09=19200 $80=2 $20=7 | $20=odd
-; $02=134.5 $0a=38400 $40=6 | $60=even
-; $03=300 $0b=57600 $60=5 | $A0=mark
-; $04=600 $0c=115200 | $E0=space
-; $05=1200 $0d=230400
-; $06=2400 $0e=future
-; $07=4800 $0f=future
-;
-
-_rs232_params:
- jsr CheckInitialized ;** check initialized
- bcc @L1
- rts
-
-; Save new parity
-
-@L1: and #%11100000
- ora #%00000001
- sta tmp2
-
-; Set baud/parameters
-
- jsr popa
- sta tmp1
- and #$0f
- tax
- lda Bauds,x
- cmp #$ff
- bne @L5
- lda #ErrBaudNotAvail
- bne @L9
-
-@L5: jsr sys_bank ; Indirect segment to system bank
- tax
- lda tmp1
- and #$0f
- sta BaudCode
- lda tmp1
- and #%11100000
- ora #%00010000
- sta tmp1
- txa
- and #$0f
- ora tmp1
- ldy #RegControl
- sta (acia),y
-
-; Set new parity
-
-@L7: lda tmp2
- sta RtsOff
- ora #%00001000
- ldy #RegCommand
- sta (acia),y
- jsr restore_bank ; Restore indirect bank
- lda #0
-@L9: ldx #0
- rts
-
-.rodata
-Bauds:
- .byte $01,$03,$04,$06,$07,$08,$0a,$0c,$0e,$0f,$ff,$ff,$ff,$ff,$ff,$ff
- ;in: 0 1 2 3 4 5 6 7 8 9 a b c d e f
- ;baud50 110 134 3 6 12 24 48 96 19 38 57 115 230 exp exp
- ;out masks: $0F=Baud, val$FF=err
-.code
-
-;----------------------------------------------------------------------------
-;
-; unsigned char __fastcall__ rs232_done (void);
-; /* Close the port, deinstall the interrupt hander. You MUST call this function
-; * before terminating the program, otherwise the machine may crash later. If
-; * in doubt, install an exit handler using atexit(). The function will do
-; * nothing, if it was already called.
-; */
-;
-
-
-_rs232_done:
- bit Initialized ;** check initialized
- bpl @L9
-
-; Stop interrupts, drop DTR
-
- lda RtsOff
- and #%11100010
- ora #%00000010
- ldx IndReg
- ldy #$0F
- sty IndReg ; Set indirect to system bank
- ldy #RegCommand
- sta (acia),y
- stx IndReg ; Restore old indirect bank
-
-; Flag uninitialized
-
-@L9: lda #$00
- sta Initialized
- tax
- rts
-
-;----------------------------------------------------------------------------
-;
-; unsigned char __fastcall__ rs232_get (char* B);
-; /* Get a character from the serial port. If no characters are available, the
-; * function will return RS_ERR_NO_DATA, so this is not a fatal error.
-; */
-;
-
-_rs232_get:
- jsr CheckInitialized ; Check if initialized
- bcc @L1
- rts
-
-; Check for bytes to send
-
-@L1: sta ptr1
- stx ptr1+1 ; Store pointer to received char
- ldx SendFreeCnt
- cpx #$ff
- beq @L2
- lda #$00
- jsr TryToSend
-
-; Check for buffer empty
-
-@L2: lda RecvFreeCnt
- cmp #$ff
- bne @L3
- lda #ErrNoData
- ldx #0
- rts
-
-; Check for flow stopped & enough free: release flow control
-
-@L3: ldx Stopped
- beq @L4
- cmp #63
- bcc @L4
- lda #$00
- sta Stopped
- lda RtsOff
- ora #%00001000
- ldx IndReg
- ldy #$0F ; Set indirect to system bank
- sty IndReg
- ldy #RegCommand
- sta (acia),y
- stx IndReg
-
-; Get byte from buffer
-
-@L4: ldx IndReg
- lda #BufferSeg ; Set indirect to buffer bank
- sta IndReg
- ldy RecvHead
- lda (RecvBuf),y
- stx IndReg ; Restore indirect bank
- inc RecvHead
- inc RecvFreeCnt
- ldx #$00
- sta (ptr1,x)
- txa ; Return code = 0
- rts
-
-;----------------------------------------------------------------------------
-;
-; unsigned char __fastcall__ rs232_put (char B);
-; /* Send a character via the serial port. There is a transmit buffer, but
-; * transmitting is not done via interrupt. The function returns
-; * RS_ERR_OVERFLOW if there is no space left in the transmit buffer.
-; */
-;
-
-_rs232_put:
- jsr CheckInitialized ; Check initialized
- bcc @L1
- rts
-
-; Try to send
-
-@L1: ldx SendFreeCnt
- cpx #$ff
- beq @L2
- pha
- lda #$00
- jsr TryToSend
- pla
-
-; Put byte into send buffer & send
-
-@L2: ldx SendFreeCnt
- bne @L3
- lda #ErrOverflow
- ldx #$00
- rts
-
-; There is enough room (character still in A)
-
-@L3: ldx IndReg
- ldy #BufferSeg ; Set indirect to buffer segment
- sty IndReg
- ldy SendTail
- sta (SendBuf),y
- stx IndReg ; Restore indirect bank
- inc SendTail
- dec SendFreeCnt
- lda #$ff
- jsr TryToSend
- lda #$00
- tax
- rts
-
-;----------------------------------------------------------------------------
-;
-; unsigned char __fastcall__ rs232_pause (void);
-; /* Assert flow control and disable interrupts. */
-;
-
-_rs232_pause:
-; Check initialized
- jsr CheckInitialized
- bcc @L1
- rts
-
-; Assert flow control
-
-@L1: lda RtsOff
- sta Stopped
- jsr sys_bank ; Set indirect to system bank
- ldy #RegCommand
- sta (acia),y
-
-; Delay for flow stop to be received
-
- ldx BaudCode
- lda PauseTimes,x
- jsr DelayMs
-
-; Stop rx interrupts
-
- lda RtsOff
- ora #$02
- ldy #RegCommand
- sta (acia),y
- jsr restore_bank ; Restore indirect segment
- lda #0
- tax
- rts
-
-
-.rodata
-; Delay times: 32 byte-receive times in milliseconds, or 100 max.
-; Formula = 320,000 / baud
-PauseTimes:
- .byte 100,100,100,100,100,100,100,067,034,017,009,006,003,002,001,001
- ;in: 0 1 2 3 4 5 6 7 8 9 a b c d e f
- ;baud50 110 134 3 6 12 24 48 96 19 38 57 115 230 exp exp
-.code
-
-;----------------------------------------------------------------------------
-;
-; unsigned char __fastcall__ rs232_unpause (void);
-; /* Re-enable interrupts and release flow control */
-;
-
-_rs232_unpause:
-; Check initialized
- jsr CheckInitialized
- bcc @L1
- rts
-
-; Re-enable rx interrupts & release flow control
-
-@L1: lda #$00
- sta Stopped
- lda RtsOff
- ora #%00001000
- ldx IndReg
- ldy #$0F
- sty IndReg ; Set indirect to system bank
- ldy #RegCommand
- sta (acia),y
- stx IndReg ; Restore indirect bank
-
-; Poll for stalled char & exit
-
- jsr PollReceive
- lda #0
- tax
- rts
-
-;----------------------------------------------------------------------------
-;
-; unsigned char __fastcall__ rs232_status (unsigned char* status,
-; unsigned char* errors);
-; /* Return the serial port status. */
-;
-
-_rs232_status:
- sta ptr2
- stx ptr2+1
- jsr popax
- sta ptr1
- stx ptr1+1
- jsr CheckInitialized
- bcs @L9
-
-; Get status
-
- ldx IndReg ; Save indirect segment
- lda #$0F
- sta IndReg ; Set system bank as indirect segment
- ldy #RegStatus
- lda (acia),y ; Read status register
- stx IndReg
- ldy #0
- sta (ptr1),y
- jsr PollReceive ; bug-recovery hack
- lda Errors
- ldy #0
- sta (ptr2),y
- tya
- tax
-@L9: rts
-
-;----------------------------------------------------------------------------
-;
-; RS232 interrupt handler.
-; The RS232 handler will be called with the system bank as indirect bank
-; and all registers saved.
-;
-
-k_rs232:
- ldy #RegStatus
- lda (acia),y ; check for byte received
- and #$08
- beq @L9 ; Nothing to receive
- lda (acia),y ; check for receive errors
- and #$07
- beq @L1
- inc Errors
-@L1: ldy #RegData
- lda (acia),y ; get byte and put into receive buffer
- ldx RecvFreeCnt
- beq @L3
- ldy #BufferSeg
- sty IndReg
- ldy RecvTail
- sta (RecvBuf),y ; Store received character
- lda #$0F
- sta IndReg ; Restore indirect segment
- inc RecvTail
- dec RecvFreeCnt
- cpx #33 ; check for buffer space low
- bcs @L9
-
-; Assert flow control
-
-@L2: lda RtsOff ; assert flow control if buffer space too low
- ldy #RegCommand
- sta (acia),y
- sta Stopped
- rts
-
-; Drop this char
-
-@L3: inc DropCnt+0 ;not time-critical
- bne @L9
- inc DropCnt+1
- bne @L9
- inc DropCnt+2
- bne @L9
- inc DropCnt+3
-@L9: rts
-
-
-;----------------------------------------------------------------------------
-;
-; CheckInitialized - internal check if initialized
-; Set carry and an error code if not initialized, clear carry and do not
-; change any registers if initialized.
-;
-
-CheckInitialized:
- bit Initialized
- bmi @L1
- lda #ErrNotInitialized
- ldx #0
- sec
- rts
-
-@L1: clc
- rts
-
-;----------------------------------------------------------------------------
-; Try to send a byte. Internal routine. A = TryHard
-
-TryToSend:
- sta tmp1 ; Remember tryHard flag
- ldx IndReg ; Save indirect segment
- lda #$0F
- sta IndReg ; Set system segment as indirect segment
-@L0: lda SendFreeCnt
- cmp #$ff
- beq @L3 ; Bail out
-
-; Check for flow stopped
-
-@L1: lda Stopped
- bne @L3 ; Bail out
-
-; Check that the UART is ready to send
-
-@L2: ldy #RegStatus
- lda (acia),y
- and #$10
- bne @L4
- bit tmp1 ; Keep trying if must try hard
- bmi @L0
-@L3: stx IndReg ; Restore indirect segment
- rts
-
-; Send byte and try again
-
-@L4: lda #BufferSeg
- sta IndReg
- ldy SendHead
- lda (SendBuf),y
- ldy #$0F
- sty IndReg
- ldy #RegData
- sta (acia),y
- inc SendHead
- inc SendFreeCnt
- jmp @L0
-
-
-;----------------------------------------------------------------------------
-;
-; PollReceive - poll for rx char
-; This function is useful in odd cases where the 6551 has a character in
-; it but it fails to raise an NMI. It might be edge-triggering conditions?
-; Actually, I'm not entirely sure that this condition can still arrise, but
-; calling this function does no harm.
-;
-
-PollReceive:
- ldx IndReg ; Save indirect segment
- lda #$0F
- sta IndReg ; Set system bank as indirect segment
- ldy #RegStatus
- lda (acia),y
- and #$08
- beq @L9
- lda (acia),y ; Read a second time? ###
- and #$08
- beq @L9
- ldy #RegData
- lda (acia),y
- ldy RecvFreeCnt
- beq @L9
- ldy #BufferSeg
- sty IndReg
- ldy RecvTail
- sta (RecvBuf),y
- inc RecvTail
- dec RecvFreeCnt
-@L9: stx IndReg ; Restore indirect segment
- rts
-
-;----------------------------------------------------------------------------
-;
-; DelayMs : delay for given number of milliseconds
-; This implementation isn't very rigerous; it merely delays for the
-; approximate number of clock cycles for the processor speed.
-; Algorithm:
-; repeat for number of milliseconds:
-; repeat for number of MHz of cpu speed:
-; delay for 1017 clock cycles
-;
-
-DelayMs: ;( .A=milliseconds )
-@L1: ldy #1 ; 1MHz
-@L2: ldx #203 ;(2)
-@L3: dex ;(2)
- bne @L3 ;(3) // 1017 cycles
- dey
- bne @L2
- sec
- sbc #1
- bne @L1
- rts
-
-.end
-
-
-
projects / cc65 / commitdiff