--- /dev/null
+;
+; DriveWire sector routines
+;
+; Copyright 2015 Tormod Volden
+; Copyright 2008 Boisy G. Pitre
+; Distributed under the GNU General Public License, version 2 or later.
+;
+
+ ; exported
+ .globl _dw_operation
+ .globl _dw_reset
+ .globl _dw_transaction
+
+ .globl _dw_lpr
+ .globl _dw_lpr_close
+ .globl _dw_rtc_read
+
+
+ ; imported
+ .globl map_process
+ .globl map_process_always
+ .globl map_kernel
+
+ .area .common
+
+_dw_transaction:
+ pshs cc,y ; save caller
+ orcc #0x50 ; stop interrupts
+ tstb ; rawflag?
+ beq skip@ ; nope - then skip switching to process map
+ jsr map_process_always
+skip@ ldy 5,s ; Y = number of bytes to send
+ beq ok@ ; no bytes to write - leave
+ jsr DWWrite ; send to DW
+ ldx 7,s ; X is receive buffer
+ ldy 9,s ; Y = number of bytes to receive
+ beq ok@ ; no bytes to send - leave
+ jsr DWRead ; read in that many bytes
+ bcs frame@ ; C set on framing error
+ bne part@ ; Z zet on all bytes received
+ok@ ldx #0 ; no error
+out@ jsr map_kernel
+ puls cc,y,pc ; return
+frame@ ldx #-1 ; frame error
+ bra out@
+part@ ldx #-2 ; not all bytes received!
+ bra out@
+
+_dw_reset:
+ ; maybe reinitalise PIA here?
+ ; and send DW_INIT request to server?
+ rts
+
+_dw_operation:
+ pshs y,x
+ ; get parameters from C, X points to cmd packet
+ ldx 6,x ; page map
+ jsr map_process ; kernel if zero
+ puls x
+ lda 5,x ; minor = drive number
+ ldb ,x ; write flag
+ ; buffer location into Y
+ ldy 3,x
+ ; sector number into X
+ ldx 1,x
+ tstb
+ bne @write
+ jsr dw_read_sector
+ bra @done
+@write jsr dw_write_sector
+@done bcs @err
+ bne @err
+ ldx #0
+@fin jsr map_kernel
+@ret puls y,pc
+@err ldx #0xFFFF
+ bra @fin
+
+; Write a sector to the DriveWire server
+; Drive number in A, sector number in X, buffer location in Y
+; Sets carry or non-zero flags on error
+dw_write_sector:
+ ; header: OP, drive = A, LSN 23-16 = 0, LSN 15-8 and LSN 7-0 = X
+ clrb
+ pshs a,b,x
+ ldb #OP_WRITE
+ pshs b
+ ; send header
+ tfr s,x
+ pshs y ; save buffer location
+ ldy #5
+ jsr DWWrite
+ ; send payload
+ ldx ,s
+ ldy #256
+ jsr DWWrite
+ ; calculate checksum of payload, backwards
+ exg x,y ; Y is zero after DWWrite
+@sum ldb ,-y
+ abx
+ cmpy ,s ; buffer location start
+ bne @sum
+ stx ,s ; checksum to send
+ tfr s,x
+ ldy #2
+ jsr DWWrite
+ ; get status byte from server into following byte
+ ldy #1
+ clra ; clear carry bit for BECKER variant
+ jsr DWRead
+ leas 7,s
+ bcs @ret
+ bne @ret
+ ldb -5,s ; received status byte (zero is success)
+@ret rts
+
+;
+; Based on "DoRead" by Boisy G. Pitre from DWDOS hosted on toolshed.sf.net
+; Read a sector from the DriveWire server
+; Drive number in A, 16-bit sector in X, buffer location in Y
+; Sets carry or non-zero flags on error
+
+dw_read_sector:
+ ; header: OP, drive = A, LSN 23-16 = 0, LSN 15-8 and LSN 7-0 = X
+ clrb
+ pshs d,x,y
+ lda #OP_READEX
+ReRead pshs a
+ leax ,s
+ ldy #$0005
+ lbsr DWWrite
+ puls a
+ ldx 4,s ; get read buffer pointer
+ ldy #256 ; read 256 bytes
+ ldd #133*1 ; 1 second timeout
+ bsr DWRead
+ bcs ReadEx
+ bne ReadEx
+; Send 2 byte checksum
+ pshs y
+ leax ,s
+ ldy #2
+ lbsr DWWrite
+ ldy #1
+ ldd #133*1
+ bsr DWRead
+ leas 2,s
+ bcs ReadEx
+ bne ReadEx
+; Check received status byte
+ lda ,s
+ beq ReadEx
+ cmpa #E_CRC
+ bne ReadErr
+ lda #OP_REREADEX
+ clr ,s
+ bra ReRead
+ReadErr comb ; set carry bit
+ReadEx puls d,x,y,pc
+
+ .area .text
+;
+; Virtual devices on DriveWire
+;
+; Line printer
+; RTC
+; Virtual serial ???
+;
+;
+; dw_lpr(uint8_t c)
+;
+; Print a byte to drive wire printers
+;
+; B holds the byte. Call with interrupts off
+;
+_dw_lpr:
+ pshs y
+ stb lprb2
+ ldx #lprb
+ ldy #2
+dwop:
+ jsr DWWrite
+ puls y,pc
+
+;
+; dw_lpr_close(void)
+;
+; Close the printer device
+;
+_dw_lpr_close:
+ pshs y
+ ldx #lprb3
+ ldy #1
+ bra dwop
+
+;
+; uint8_t dw_rtc_read(uint8_t *p)
+;
+_dw_rtc_read:
+ pshs y
+ ldy #2
+ pshs x
+ ldx #lprrtw
+ jsr DWWrite
+ puls x
+ ldy #6
+ clra
+ jsr DWRead
+ clrb
+ sbcb #0
+ bra dwop
+
+ .area .data
+
+lprb: .db 0x50 ; print char
+lprb2: .db 0x00 ; filled in with byte to send
+lprb3: .db 0x46 ; printer flush
+lprrtw: .db 0x23 ; request for time
+
+ .area .common
+
+
+; Used by DWRead and DWWrite
+IntMasks equ $50
+NOINTMASK equ 1
+
+; Hardcode these for now so that we can use below files unmodified
+; "BECKER" is defined through our Makefile
+H6309 equ 0
+ARDUINO equ 0
+JMCPBCK equ 0
+BAUD38400 equ 0
+
+; These files are copied almost as-is from HDB-DOS
+ *PRAGMA nonewsource
+ include "../dev/drivewire/dw-6809.def"
+ include "../dev/drivewire/dwread-6809.s"
+ include "../dev/drivewire/dwwrite-6809.s"
+
public / FUZIX.git / commitdiff