mirror of
https://github.com/cc65/cc65.git
synced 2024-06-26 05:29:30 +00:00
38f7daf40e
The Pascal Firmware Protocol Bytes ID are not enough to differentiate an SSC card from a IIgs serial firmware: http://www.1000bit.it/support/manuali/apple/technotes/misc/tn.misc.08.html Loading a2(e).ssc.ser on a IIgs succeeds, then goes to limbo when one tries to use the serial port. Check first byte on the slot's firmware in addition to the four existing ones, as it's supposed to be $2C (BIT instruction) on an SSC card, and $EF (65C816 SEP instruction) on the IIgs' serial firmware (ROM revisions 0, 1, 3).
478 lines
15 KiB
ArmAsm
478 lines
15 KiB
ArmAsm
;
|
|
; Serial driver for the Apple II Super Serial Card.
|
|
;
|
|
; Oliver Schmidt, 21.04.2005
|
|
;
|
|
; 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 "ser-kernel.inc"
|
|
.include "ser-error.inc"
|
|
|
|
.macpack module
|
|
.macpack cpu
|
|
|
|
; ------------------------------------------------------------------------
|
|
; Header. Includes jump table
|
|
|
|
.ifdef __APPLE2ENH__
|
|
module_header _a2e_ssc_ser
|
|
.else
|
|
module_header _a2_ssc_ser
|
|
.endif
|
|
|
|
; Driver signature
|
|
.byte $73, $65, $72 ; "ser"
|
|
.byte SER_API_VERSION ; Serial API version number
|
|
|
|
; Library reference
|
|
.addr $0000
|
|
|
|
; Jump table
|
|
.addr SER_INSTALL
|
|
.addr SER_UNINSTALL
|
|
.addr SER_OPEN
|
|
.addr SER_CLOSE
|
|
.addr SER_GET
|
|
.addr SER_PUT
|
|
.addr SER_STATUS
|
|
.addr SER_IOCTL
|
|
.addr SER_IRQ
|
|
|
|
;----------------------------------------------------------------------------
|
|
; I/O definitions
|
|
|
|
.if (.cpu .bitand CPU_ISET_65C02)
|
|
ACIA = $C088
|
|
.else
|
|
Offset = $8F ; Move 6502 false read out of I/O to page $BF
|
|
ACIA = $C088-Offset
|
|
.endif
|
|
|
|
ACIA_DATA = ACIA+0 ; Data register
|
|
ACIA_STATUS = ACIA+1 ; Status register
|
|
ACIA_CMD = ACIA+2 ; Command register
|
|
ACIA_CTRL = ACIA+3 ; Control register
|
|
|
|
;----------------------------------------------------------------------------
|
|
; 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 ;
|
|
|
|
RecvBuf: .res 256 ; Receive buffers: 256 bytes
|
|
SendBuf: .res 256 ; Send buffers: 256 bytes
|
|
|
|
Index: .res 1 ; I/O register index
|
|
|
|
.data
|
|
|
|
Slot: .byte $02 ; Default to SSC in slot 2
|
|
|
|
.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
|
|
|
|
; (*): The first byte we'll check at offset 0 is
|
|
; expected to be a BIT instruction on any Apple2
|
|
; machine with an ACIA 6551, including the //c
|
|
; and //c+.
|
|
; The IIgs, on the other hand, has a
|
|
; Zilog Z8530 chip and its firmware starts with
|
|
; a SEP instruction. We don't want to load this
|
|
; driver on the IIgs' serial port.
|
|
;
|
|
; The next four bytes we check are the Pascal
|
|
; Firmware Protocol Bytes that identify a
|
|
; serial card.
|
|
|
|
IdOfsTable:
|
|
.byte $00 ; First instruction
|
|
.byte $05 ; Pascal 1.0 ID byte
|
|
.byte $07 ; Pascal 1.0 ID byte
|
|
.byte $0B ; Pascal 1.1 generic signature byte
|
|
.byte $0C ; Device signature byte
|
|
IdValTable:
|
|
.byte $2C ; BIT
|
|
.byte $38 ; ID Byte 0 (from Pascal 1.0), fixed
|
|
.byte $18 ; ID Byte 1 (from Pascal 1.0), fixed
|
|
.byte $01 ; Generic signature for Pascal 1.1, fixed
|
|
.byte $31 ; Device signature byte (serial or
|
|
; parallel I/O card type 1)
|
|
|
|
IdTableLen = * - IdValTable
|
|
|
|
.code
|
|
|
|
;----------------------------------------------------------------------------
|
|
; SER_INSTALL: Is called after the driver is loaded into memory. If possible,
|
|
; check if the hardware is present. Must return an SER_ERR_xx code in a/x.
|
|
;
|
|
; Since we don't have to manage the IRQ vector on the Apple II, this is
|
|
; actually the same as:
|
|
;
|
|
; SER_UNINSTALL: Is called before the driver is removed from memory.
|
|
; No return code required (the driver is removed from memory on return).
|
|
;
|
|
; and:
|
|
;
|
|
; SER_CLOSE: Close the port and disable interrupts. Called without parameters.
|
|
; Must return an SER_ERR_xx code in a/x.
|
|
|
|
SER_INSTALL:
|
|
SER_UNINSTALL:
|
|
SER_CLOSE:
|
|
ldx Index ; Check for open port
|
|
beq :+
|
|
|
|
; Deactivate DTR and disable 6551 interrupts
|
|
lda #%00001010
|
|
sta ACIA_CMD,x
|
|
|
|
; Done, return an error code
|
|
: lda #SER_ERR_OK
|
|
.assert SER_ERR_OK = 0, error
|
|
tax
|
|
stx Index ; Mark port as closed
|
|
rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; SER_OPEN: A pointer to a ser_params structure is passed in ptr1.
|
|
; Must return an SER_ERR_xx code in a/x.
|
|
|
|
SER_OPEN:
|
|
ldx #<$C000
|
|
stx ptr2
|
|
lda #>$C000
|
|
ora Slot
|
|
sta ptr2+1
|
|
|
|
; Check Pascal 1.1 Firmware Protocol ID bytes
|
|
: ldy IdOfsTable,x
|
|
lda IdValTable,x
|
|
cmp (ptr2),y
|
|
bne NoDevice
|
|
inx
|
|
cpx #IdTableLen
|
|
bcc :-
|
|
|
|
; Convert slot to I/O register index
|
|
lda Slot
|
|
asl
|
|
asl
|
|
asl
|
|
asl
|
|
.if .not (.cpu .bitand CPU_ISET_65C02)
|
|
adc #Offset ; Assume carry to be clear
|
|
.endif
|
|
tax
|
|
|
|
; 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
|
|
ldy #$00
|
|
sty Stopped
|
|
sty RecvHead
|
|
sty RecvTail
|
|
sty SendHead
|
|
sty SendTail
|
|
dey ; Y = 255
|
|
sty RecvFreeCnt
|
|
sty SendFreeCnt
|
|
|
|
; Set the value for the control register, which contains stop bits,
|
|
; word length and the baud rate.
|
|
ldy #SER_PARAMS::BAUDRATE
|
|
lda (ptr1),y ; Baudrate index
|
|
tay
|
|
lda BaudTable,y ; Get 6551 value
|
|
bmi InvBaud ; Branch if rate not supported
|
|
sta tmp1
|
|
|
|
ldy #SER_PARAMS::DATABITS ; Databits
|
|
lda (ptr1),y
|
|
tay
|
|
lda BitTable,y
|
|
ora tmp1
|
|
sta tmp1
|
|
|
|
ldy #SER_PARAMS::STOPBITS ; Stopbits
|
|
lda (ptr1),y
|
|
tay
|
|
lda StopTable,y
|
|
ora tmp1
|
|
ora #%00010000 ; Receiver clock source = baudrate
|
|
sta ACIA_CTRL,x
|
|
|
|
; Set the value for the command register. We remember the base value
|
|
; in RtsOff, since we will have to manipulate ACIA_CMD often.
|
|
ldy #SER_PARAMS::PARITY ; Parity
|
|
lda (ptr1),y
|
|
tay
|
|
lda ParityTable,y
|
|
ora #%00000001 ; DTR active
|
|
sta RtsOff
|
|
ora #%00001000 ; Enable receive interrupts
|
|
sta ACIA_CMD,x
|
|
|
|
; Done
|
|
stx Index ; Mark port as open
|
|
lda #SER_ERR_OK
|
|
.assert SER_ERR_OK = 0, error
|
|
tax
|
|
rts
|
|
|
|
; Device (hardware) not found
|
|
NoDevice:lda #SER_ERR_NO_DEVICE
|
|
ldx #0 ; return value is char
|
|
rts
|
|
|
|
; Invalid parameter
|
|
InvParam:lda #SER_ERR_INIT_FAILED
|
|
ldx #0 ; return value is char
|
|
rts
|
|
|
|
; Baud rate not available
|
|
InvBaud:lda #SER_ERR_BAUD_UNAVAIL
|
|
ldx #0 ; return value is char
|
|
rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; SER_GET: Will fetch a character from the receive buffer and store it into the
|
|
; variable pointed to by ptr1. If no data is available, SER_ERR_NO_DATA is
|
|
; returned.
|
|
|
|
SER_GET:
|
|
ldx Index
|
|
|
|
; Check for buffer empty
|
|
lda RecvFreeCnt ; (25)
|
|
cmp #$FF
|
|
bne :+
|
|
lda #SER_ERR_NO_DATA
|
|
ldx #0 ; return value is char
|
|
rts
|
|
|
|
; Check for flow stopped & enough free: release flow control
|
|
: ldy Stopped ; (34)
|
|
beq :+
|
|
cmp #63
|
|
bcc :+
|
|
lda #$00
|
|
sta Stopped
|
|
lda RtsOff
|
|
ora #%00001000
|
|
sta ACIA_CMD,x
|
|
|
|
; Get byte from buffer
|
|
: ldy RecvHead ; (41)
|
|
lda RecvBuf,y
|
|
inc RecvHead
|
|
inc RecvFreeCnt
|
|
ldx #$00 ; (59)
|
|
.if (.cpu .bitand CPU_ISET_65C02)
|
|
sta (ptr1)
|
|
.else
|
|
sta (ptr1,x)
|
|
.endif
|
|
txa ; Return code = 0
|
|
rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; SER_PUT: Output character in A.
|
|
; Must return an SER_ERR_xx code in a/x.
|
|
|
|
SER_PUT:
|
|
ldx Index
|
|
|
|
; Try to send
|
|
ldy SendFreeCnt
|
|
cpy #$FF ; Nothing to flush
|
|
beq :+
|
|
pha
|
|
lda #$00 ; TryHard = false
|
|
jsr TryToSend
|
|
pla
|
|
|
|
; Reload SendFreeCnt after TryToSend
|
|
ldy SendFreeCnt
|
|
bne :+
|
|
lda #SER_ERR_OVERFLOW
|
|
ldx #0 ; return value is char
|
|
rts
|
|
|
|
; Put byte into send buffer & send
|
|
: ldy SendTail
|
|
sta SendBuf,y
|
|
inc SendTail
|
|
dec SendFreeCnt
|
|
lda #$FF ; TryHard = true
|
|
jsr TryToSend
|
|
lda #SER_ERR_OK
|
|
.assert SER_ERR_OK = 0, error
|
|
tax
|
|
rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; SER_STATUS: Return the status in the variable pointed to by ptr1.
|
|
; Must return an SER_ERR_xx code in a/x.
|
|
|
|
SER_STATUS:
|
|
ldx Index
|
|
lda ACIA_STATUS,x
|
|
ldx #$00
|
|
sta (ptr1,x)
|
|
.assert SER_ERR_OK = 0, error
|
|
txa
|
|
rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; SER_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 SER_ERR_xx code in a/x.
|
|
|
|
SER_IOCTL:
|
|
; Check data msb and code to be 0
|
|
ora ptr1+1
|
|
bne :+
|
|
|
|
; Check data lsb to be [1..7]
|
|
ldx ptr1
|
|
beq :+
|
|
cpx #7+1
|
|
bcs :+
|
|
|
|
stx Slot
|
|
.assert SER_ERR_OK = 0, error
|
|
tax
|
|
rts
|
|
|
|
: lda #SER_ERR_INV_IOCTL
|
|
ldx #0 ; return value is char
|
|
rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; SER_IRQ: Called from the builtin runtime IRQ handler as a subroutine. All
|
|
; registers are already saved, no parameters are passed, but the carry flag
|
|
; is clear on entry. The routine must return with carry set if the interrupt
|
|
; was handled, otherwise with carry clear.
|
|
|
|
SER_IRQ:
|
|
ldx Index ; Check for open port
|
|
beq Done
|
|
lda ACIA_STATUS,x ; Check ACIA status for receive interrupt
|
|
and #$08
|
|
beq Done ; Jump if no ACIA interrupt
|
|
lda ACIA_DATA,x ; Get byte from ACIA
|
|
ldx RecvFreeCnt ; Check if we have free space left
|
|
beq Flow ; Jump if no space in receive buffer
|
|
ldy RecvTail ; Load buffer pointer
|
|
sta RecvBuf,y ; Store received byte in buffer
|
|
inc RecvTail ; Increment buffer pointer
|
|
dec RecvFreeCnt ; Decrement free space counter
|
|
cpx #33 ; Check for buffer space low
|
|
bcc Flow ; Assert flow control if buffer space low
|
|
rts ; Interrupt handled (carry already set)
|
|
|
|
; Assert flow control if buffer space too low
|
|
Flow: ldx Index
|
|
lda RtsOff
|
|
sta ACIA_CMD,x
|
|
sta Stopped
|
|
sec ; Interrupt handled
|
|
Done: rts
|
|
|
|
;----------------------------------------------------------------------------
|
|
; Try to send a byte. Internal routine. A = TryHard
|
|
|
|
TryToSend:
|
|
sta tmp1 ; Remember tryHard flag
|
|
NextByte:
|
|
lda SendFreeCnt
|
|
cmp #$FF
|
|
beq Quit ; Bail out
|
|
|
|
; Check for flow stopped
|
|
Again: lda Stopped
|
|
bne Quit ; Bail out
|
|
|
|
; Check that ACIA is ready to send
|
|
lda ACIA_STATUS,x
|
|
and #$10
|
|
bne Send
|
|
bit tmp1 ; Keep trying if must try hard
|
|
bmi Again
|
|
Quit: rts
|
|
|
|
; Send byte and try again
|
|
Send: ldy SendHead
|
|
lda SendBuf,y
|
|
sta ACIA_DATA,x
|
|
inc SendHead
|
|
inc SendFreeCnt
|
|
jmp NextByte
|