Power-Programmierung/CD1.mdf/lan/drivrs30/wd8003e.asm

Assembly Source File | 1989-06-08 | 25KB | 767 lines

version    equ    2

    include    defs.asm

;   PC/FTP Packet Driver source, conforming to version 1.05 of the spec
;   Updated to version 1.08 Feb. 17, 1989 by Russell Nelson.
;   Robert C Clements, K1BC,  August 19, 1988
;   Portions (C) Copyright 1988 Robert C Clements

;   This program is free software; you can redistribute it and/or modify
;   it under the terms of the GNU General Public License as published by
;   the Free Software Foundation, version 1.
;
;   This program is distributed in the hope that it will be useful,
;   but WITHOUT ANY WARRANTY; without even the implied warranty of
;   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;   GNU General Public License for more details.
;
;   You should have received a copy of the GNU General Public License
;   along with this program; if not, write to the Free Software
;   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

code    segment    byte public
    assume    cs:code, ds:code

HT    equ    09h
CR    equ    0dh
LF    equ    0ah

;
;  Packet Driver Error numbers
BAD_HANDLE    equ    1        ;invalid handle number
NO_CLASS    equ    2        ;no interfaces of specified class found
NO_TYPE        equ    3        ;no interfaces of specified type found
NO_NUMBER    equ    4        ;no interfaces of specified number found
BAD_TYPE    equ    5        ;bad packet type specified
NO_MULTICAST    equ    6        ;this interface does not support
CANT_TERMINATE    equ    7        ;this packet driver cannot terminate
BAD_MODE    equ    8        ;an invalid receiver mode was specified
NO_SPACE    equ    9        ;operation failed because of insufficient
TYPE_INUSE    equ    10        ;the type had previously been accessed,
BAD_COMMAND    equ    11        ;the command was out of range, or not
CANT_SEND    equ    12        ;the packet couldn't be sent (usually

; Stuff specific to the Western Digital WD003E Ethernet controller board
; C version by Bob Clements, K1BC, May 1988 for the KA9Q TCP/IP package
; Symbol prefix "EW" is for Ethernet, Western-digital card

; The EW registers - First, the board registers */

EW_CMD        equ    000h    ; Board's command register
EW_SAPROM    equ    008h    ; Window on station addr prom

; The EW registers - Next, the DS8390 chip registers */
; There are two (really 3) pages of registers in the chip. You select
; which page you want, then address them at offsets 10-1F from base.
; The chip command register (EW_CCMD) appears in both pages.

EW_CCMD        equ    010h    ; Chip's command register

; Page 0

EW0_STARTPG    equ    011h    ; Starting page of ring bfr
EW0_STOPPG    equ    012h    ; Ending page +1 of ring bfr
EW0_BOUNDARY    equ    013h    ; Boundary page of ring bfr
EW0_TSR        equ    014h    ; Transmit status reg
EW0_TPSR    equ    014h    ; Transmit starting page
EW0_TCNTLO    equ    015h    ; Low  byte of tx byte count
EW0_TCNTHI    equ    016h    ; High byte of tx byte count
EW0_ISR        equ    017h    ; Interrupt status reg
EW0_RCNTLO    equ    01ah    ; Remote byte count reg
EW0_RCNTHI    equ    01bh    ; Remote byte count reg
EW0_RXCR    equ    01ch    ; RX control reg
EW0_TXCR    equ    01dh    ; TX control reg
EW0_COUNTER0    equ    01dh    ; Rcv alignment error counter
EW0_DCFG    equ    01eh    ; Data configuration reg
EW0_COUNTER1    equ    01eh    ; Rcv CRC error counter
EW0_IMR        equ    01fh    ; Interrupt mask reg
EW0_COUNTER2    equ    01fh    ; Rcv missed frame error counter

; Page 1

EW1_PHYS    equ    011h    ; This board's physical enet addr
EW1_CURPAG    equ    017h    ; Current memory page
EW1_MULT    equ    018h    ; Desired multicast addr


; Board commands in EW_CMD
EW_RESET    equ    080h    ; Reset the board
EW_MEMEN    equ    040h    ; Enable the shared memory
EW_MEM_MASK    equ    03fh    ; B18-B13 of address of the shared memory

; Chip commands in EW_CCMD
EWC_STOP    equ    001h    ; Stop the chip
EWC_START    equ    002h    ; Start the chip
EWC_TRANS    equ    004h    ; Transmit a frame
EWC_NODMA    equ    020h    ; No remote DMA used on this card
EWC_PAGE0    equ    000h    ; Select page 0 of chip registers
EWC_PAGE1    equ    040h    ; Select page 1 of chip registers

; Commands for RX control reg
EWRXCR_MON    equ    020h    ; Monitor mode
EWRXCR_BCST    equ    004h    ; Accept broadcasts

; Commands for TX control reg
EWTXCR_LOOP    equ    002h    ; Set loopback mode

; Bits in EW0_DCFG - Data config register
EWDCFG_BM8    equ    048h    ; Set burst mode, 8 deep FIFO

; Bits in EW0_ISR - Interrupt status register
EWISR_RX    equ    001h    ; Receiver, no error
EWISR_TX    equ    002h    ; Transmitter, no error
EWISR_RX_ERR    equ    004h    ; Receiver, with error
EWISR_TX_ERR    equ    008h    ;    Transmitter, with error
EWISR_OVER    equ    010h    ; Receiver overwrote the ring
EWISR_COUNTERS    equ    020h    ; Counters need emptying
EWISR_RESET    equ    080h    ; Reset completed
EWISR_ALL    equ    03fh    ; Interrupts we will enable

; Bits in received packet status byte and EW0_RSR
EWPS_RXOK    equ    001h    ; Received a good packet

; Bits in TX status reg

EWTSR_COLL    equ    004h    ; Collided at least once
EWTSR_COLL16    equ    008h    ; Collided 16 times and was dropped
EWTSR_FU    equ    020h    ; TX FIFO Underrun

; Shared memory management parameters

XMIT_MTU    equ    600h    ; Largest packet we have room for.
SM_TSTART_PG    equ    0    ; First page of TX buffer
SM_RSTART_PG    equ    6    ; Starting page of ring
SM_RSTOP_PG    equ    32    ; Last page +1 of ring
SM_BASE        equ    0C400h    ; Default para where shared memory starts
                ; Real value set at attach time.

; Description of header of each packet in receive area of shared memory

EW_RBUF_STAT    equ    0    ; Received frame status
EW_RBUF_NXT_PG    equ    1    ; Page after this frame
EW_RBUF_SIZE_LO    equ    2    ; Length of this frame
EW_RBUF_SIZE_HI    equ    3    ; Length of this frame
EW_RBUF_NHDR    equ    4    ; Length of above header area

; End of WD8003E parameter definitions

; The following three values may be overridden from the command line.
; If they are omitted from the command line, these defaults are used.

    public    int_no, io_addr, mem_base
int_no        db    2,0,0,0        ; Interrupt level
io_addr        dw    0280h,0        ; I/O address for card (jumpers)
mem_base    dw    0c400h,0    ; Shared memory addr (software)

    public    driver_class, driver_type, driver_name
driver_class    db    1        ;from the packet spec
driver_type    db    14        ;from the packet spec
driver_name    db    'WD8003E',0    ;name of the driver.


; send_pkt: - The Transmit Frame routine

    public    send_pkt
send_pkt:
;enter with ds:si -> packet, cx = packet length.
;exit with nc if ok, or else cy if error, dh set to error number.
    assume    ds:nothing
    loadport        ; Point at chip command register
    setport EW_CCMD        ; ..
tx_wait:
    mov bx,    8000h        ; Avoid infinite loop
    in al,    dx        ; Get chip command state
    test al,EWC_TRANS    ; Is transmitter still running?
    jz    tx_idle        ; Go if free
    dec    bx        ; Count the timeout
    jnz    tx_wait        ; Fall thru if TX is stuck
                ; Should count these error timeouts
                ; Maybe need to add recovery logic here
tx_idle:
    cmp    cx,XMIT_MTU    ; Is this packet too large?
    ja    send_pkt_toobig

    cmp cx,    RUNT        ; Is the frame long enough?
    jnb    tx_oklen    ; Go if OK
    mov cx,    RUNT        ; Stretch frame to minimum allowed
tx_oklen:
    push    cx        ; Hold count for later
                ; Now compute destination of move in es:di
    mov ax,    mem_base    ; Compute base of transmit buffer
;    add ax,    SM_TSTART_PG*16    ; The right page in mem (currently zero)
    mov es,    ax        ; Paragraph of the TX buffer
    xor di,    di        ; Fill starting at beginning of paragraph

    call    movemem

    pop    cx        ; Get back count to give to board
    loadport        ; Base of I/O regs
    setport    EW0_TCNTLO    ; Low byte of TX count
    mov al,    cl        ; Get the count
    out dx,    al        ; Tell card the count
    setport    EW0_TCNTHI    ; High byte of TX count
    mov al,    ch        ; Get the count
    out dx,    al        ; Tell card the count
    setport    EW0_TPSR    ; Transmit Page Start Register
    mov al,    SM_TSTART_PG
    out dx,    al        ; Start the transmitter
    setport    EW_CCMD        ; Chip command reg
    mov al,    EWC_TRANS+EWC_NODMA
    out dx,    al        ; Start the transmitter

    clc
    ret            ; End of transmit-start routine
send_pkt_toobig:
    mov    dh,NO_SPACE
    stc
    ret


movemem:
;does the same thing as "rep movsb", only 50% faster.
;moves words instead of bytes, and handles the case of both addresses odd
;efficiently.  There is no way to handle one address odd efficiently.
;This routine always aligns the source address in the hopes that the
;destination address will also get aligned.  This is from Phil Karn's
;code from ec.c, a part of his NET package.  I bummed a few instructions
;out.
    jcxz    movemem_cnte        ; If zero, we're done already.
    test    si,1            ; Does source start on odd byte?
    jz    movemem_adre        ; Go if not
    movsb                ; Yes, move the first byte
    dec    cx            ; Count that byte
movemem_adre:
    shr    cx,1            ; convert to word count
    rep    movsw            ; Move the bulk as words
    jnc    movemem_cnte        ; Go if the count was even
    movsb                ; Move leftover last byte
movemem_cnte:
    ret


    public    get_address
get_address:
;get the address of the interface.
;enter with es:di -> place to get the address, cx = size of address buffer.
;exit with nc, cx = actual size of address, or cy if buffer not big enough.
    assume ds:code
    cmp cx,    EADDR_LEN    ; Caller wants a reasonable length?
    jb    get_addr_x    ; No, fail.
    mov cx,    EADDR_LEN    ; Yes. Set count for loop
    loadport        ; Base of device
    setport    EW_SAPROM    ; Where the address prom is
    cld            ; Make sure string mode is right
get_addr_loop:
    in al,    dx        ; Get a byte of address
    stosb            ; Feed it to caller
    inc    dx        ; Next byte at next I/O port
    loop    get_addr_loop    ; Loop over six bytes
    mov cx,    EADDR_LEN    ; Tell caller how many bytes we fed him
    clc            ; Carry off says success
    ret
get_addr_x:
    stc            ; Tell caller our addr is too big for him
    ret


    public    set_address
set_address:
    assume    ds:nothing
;enter with ds:si -> Ethernet address, CX = length of address.
;exit with nc if okay, or cy, dh=error if any errors.
;
    cmp    cx,EADDR_LEN        ;ensure that their address is okay.
    je    set_address_4
    mov    dh,BAD_ADDRESS
    stc
    jmp    short set_address_done
set_address_4:

    loadport
    setport    EW1_PHYS
set_address_1:
    lodsb
    out    dx,al
    inc    dx
    loop    set_address_1

set_address_okay:
    clc
set_address_done:
    push    cs
    pop    ds
    assume    ds:code
    ret


    public    reset_interface
reset_interface:
    assume ds:code
    loadport        ; Base of I/O regs
    setport    EW_CCMD        ; Chip command reg
    mov al,    EWC_STOP+EWC_NODMA
    out dx,    al        ; Stop the DS8390
    setport    EW0_ISR        ; Interrupt status reg
    mov al,    0ffh        ; Clear all pending interrupts
    out dx,    al        ; ..
    setport    EW0_IMR        ; Interrupt mask reg
    xor al,    al        ; Turn off all enables
    out dx,    al        ; ..
    ret


;called when we want to determine what to do with a received packet.
;enter with cx = packet length, es:di -> packet type.
;It returns with es:di = 0 if don't want this type or if no buffer available.
    extrn    recv_find: near

;called after we have copied the packet into the buffer.
;enter with ds:si ->the packet, cx = length of the packet.
    extrn    recv_copy: near

    extrn    count_in_err: near
    extrn    count_out_err: near

    public    recv
recv:
;called from the recv isr.  All registers have been saved, and ds=cs.
;Actually, not just receive, but all interrupts come here.
;Upon exit, the interrupt will be acknowledged.

    assume    ds:code
check_isr:            ; Was there an interrupt from this card?
    loadport        ; Point at interrupt status register
    setport    EW0_ISR        ; ..
    in al,    dx        ; Get pending interrupts
    and al,    EWISR_ALL    ; Any?
    jnz    isr_test_overrun
    jmp    interrupt_done    ; Go if none
; First, a messy procedure for handling the case where the rcvr
; over-runs its ring buffer.  This is spec'ed by National for the chip.
isr_test_overrun:
    test al,EWISR_OVER    ; Was there an overrun?
    jnz    recv_overrun    ; Go if so.
    jmp    recv_no_overrun    ; Go if not.
recv_overrun:
    setport    EW_CCMD        ; Stop the card
    mov al,    EWC_STOP+EWC_NODMA
    out dx,    al        ; Write "stop" to command register

; Remove one frame from the ring
    setport    EW0_BOUNDARY    ; Find end of this frame
    in al,    dx        ; Get memory page number
    inc    al        ; Page plus 1
    cmp al,    SM_RSTOP_PG    ; Wrapped around ring?
    jnz    rcv_ovr_nwrap    ; Go if not
    mov al,    SM_RSTART_PG    ; Yes, wrap the page pointer
rcv_ovr_nwrap:
    xor ah,    ah        ; Convert page to segment
    mov cl,    4
    mov bl,    al        ; Page number as arg to rcv_frm
    shl ax,    cl        ; ..
    add ax,    mem_base    ; Page in this memory
    mov es,    ax        ; Segment pointer to the frame header
    push    es        ; Hold this frame pointer for later
    mov al,    es:[EW_RBUF_STAT]    ; Get the buffer status byte
    test al,EWPS_RXOK    ; Is this frame any good?
    jz    rcv_ovr_ng    ; Skip if not
     call    rcv_frm        ; Yes, go accept it
rcv_ovr_ng:
    pop    es        ; Back to start of this frame
    mov al,    es:[EW_RBUF_NXT_PG]    ; Get pointer to next frame
    dec    al        ; Back up one page
    cmp al,    SM_RSTART_PG    ; Did it wrap?
    jge    rcv_ovr_nwr2
    mov al,    SM_RSTOP_PG-1    ; Yes, back to end of ring
rcv_ovr_nwr2:
    loadport        ; Point at boundary reg
    setport    EW0_BOUNDARY    ; ..
    out dx,    al        ; Set the boundary
    setport    EW0_RCNTLO    ; Point at byte count regs
    xor al,    al        ; Clear them
    out dx,    al        ; ..
    setport    EW0_RCNTHI
    out dx,    al
    setport    EW0_ISR        ; Point at status reg
    mov cx,    8000h        ; Timeout counter
rcv_ovr_rst_loop:
    in al,    dx        ; Is it finished resetting?
    test al,EWISR_RESET    ; ..
    jnz    rcv_ovr_rst    ; Go if so
    dec    cx        ; Loop til reset, or til timeout
    jnz    rcv_ovr_rst_loop
rcv_ovr_rst:
    loadport        ; Point at Transmit control reg
     setport    EW0_TXCR    ; ..
    mov al,    EWTXCR_LOOP    ; Put transmitter in loopback mode
    out dx,    al        ; ..
    setport    EW_CCMD        ; Point at Chip command reg
    mov al,    EWC_START+EWC_NODMA
    out dx,    al        ; Start the chip running again
    setport    EW0_TXCR    ; Back to TX control reg
    xor al,    al        ; Clear the loopback bit
    out dx,    al        ; ..
    setport    EW0_ISR        ; Point at Interrupt status register
    mov al,    EWISR_OVER    ; Clear the overrun interrupt bit
    out dx,    al        ; ..
    call    count_in_err    ; Count the anomaly
     jmp    check_isr    ; Done with the overrun case

recv_no_overrun:
; Handle receive flags, normal and with error (but not overrun).
    test al,EWISR_RX+EWISR_RX_ERR    ; Frame received without overrun?
    jnz    recv_frame    ; Go if so.
    jmp    recv_no_frame    ; Go if not.
recv_frame:
    loadport        ; Point at Chip's Command Reg
     setport    EW_CCMD        ; ..
    mov al,    EWC_NODMA+EWC_PAGE1
    out dx,    al        ; Switch to page 1 registers
    setport    EW1_CURPAG    ;Get current page of rcv ring
    in al,    dx        ; ..
    mov ah,    al        ; Hold current page in AH
     setport    EW_CCMD        ; Back to page zero registers
    mov al,    EWC_NODMA+EWC_PAGE0
    out dx,    al        ; Switch back to page 0 registers
    setport    EW0_BOUNDARY    ;Get boundary page
    in al,    dx        ; ..
    inc    al        ; Step boundary from last used page
    cmp al,    SM_RSTOP_PG    ; Wrap if needed
    jne    rx_nwrap3    ; Go if not
    mov al,    SM_RSTART_PG    ; Wrap to first RX page
rx_nwrap3:
    cmp al,    ah        ; Read all the frames?
    je    recv_frame_break    ; Finished them all
    mov bl,    al        ; Page number as arg to rcv_frm
    xor ah,    ah        ; Make segment pointer to this frame
    mov cl,    4        ; 16 * pages = paragraphs
    shl ax,    cl        ; ..
    add ax,    mem_base    ; That far into shared memory
    mov es,    ax        ; Segment part of pointer
    push    es        ; Hold on to this pointer for later
    mov al,    es:[EW_RBUF_STAT]    ; Get the buffer status byte
    test al,EWPS_RXOK    ; Good frame?
    jz    recv_no_rcv
    call    rcv_frm        ; Yes, go accept it
recv_no_rcv:
    pop    es        ; Back to base of frame
    mov al,    es:[EW_RBUF_NXT_PG]    ; Start of next frame
    dec    al        ; Make previous page for new boundary
    cmp al,    SM_RSTART_PG    ; Wrap around the bottom?
    jge    rcv_nwrap4
    mov al,    SM_RSTOP_PG-1    ; Yes
rcv_nwrap4:
    loadport        ; Point at the Boundary Reg again
     setport    EW0_BOUNDARY    ; ..
    out dx,    al        ; Set new boundary
    jmp    recv_frame    ; See if any more frames

recv_frame_break:
    loadport        ; Point at Interrupt Status Reg
     setport    EW0_ISR        ; ..
    mov al,    EWISR_RX+EWISR_RX_ERR+EWISR_OVER
    out dx,    al        ; Clear those requests
    jmp    check_isr    ; See if any other interrupts pending

recv_no_frame:                ; Handle transmit flags.
    test al,EWISR_TX+EWISR_TX_ERR    ; Frame transmitted?
    jnz    isr_tx        ; Go if so.
    jmp    isr_no_tx    ; Go if not.
isr_tx:
    mov ah,    al        ; Hold interrupt status bits
    loadport        ; Point at Transmit Status Reg
     setport    EW0_TSR        ; ..
    in al,    dx        ; ..
    test ah,EWISR_TX    ; Non-error TX?
    jz    isr_tx_err    ; No, do TX error completion
    test al,EWTSR_COLL16    ; Jammed for 16 transmit tries?
    jz    isr_tx_njam    ; Go if not
    call    count_out_err    ; Yes, count those
isr_tx_njam:
    setport    EW0_ISR        ; Clear the TX complete flag
    mov al,    EWISR_TX    ; ..
    out dx,    al        ; ..
    jmp    isr_tx_done
isr_tx_err:
    test al,EWTSR_FU    ; FIFO Underrun?
    jz    isr_txerr_nfu
    call    count_out_err    ; Yes, count those
isr_txerr_nfu:
    loadport        ; Clear the TX error completion flag
    setport    EW0_ISR        ; ..
    mov al,    EWISR_TX_ERR    ; ..
    out dx,    al        ; ..
isr_tx_done:
; If TX queue and/or TX shared memory ring buffer were being
; used, logic to step through them would go here.  However,
; in this version, we just clear the flags for background to notice.

     jmp    check_isr    ; See if any other interrupts on

isr_no_tx:
; Now check to see if any counters are getting full
    test al,EWISR_COUNTERS    ; Interrupt to handle counters?
    jnz    isr_stat    ; Go if so.
    jmp    isr_no_stat    ; Go if not.
isr_stat:
; We have to read the counters to clear them and to clear the interrupt.
; The structure of the PC/FTP driver system doesn't give us
; anything useful to do with the data, though.
    loadport        ; Point at first counter
     setport    EW0_COUNTER0    ; ..
    in al,    dx        ; Read the count, ignore it.
    setport    EW0_COUNTER1
    in al,    dx        ; Read the count, ignore it.
    setport    EW0_COUNTER2
    in al,    dx        ; Read the count, ignore it.
    setport    EW0_ISR        ; Clear the statistics completion flag
    mov al,    EWISR_COUNTERS    ; ..
    out dx,    al        ; ..
isr_no_stat:
     jmp    check_isr    ; Anything else to do?

interrupt_done:
    ret

; Do the work of copying out a receive frame.
; Called with bl/ the page number of the frame header in shared memory/
; Also, es/ the paragraph number of that page.

rcv_frm:
; Old version checked size, memory space, queue length here. Now done
; in higher level code.
; Set cx to length of this frame.
    mov ch,    es:[EW_RBUF_SIZE_HI]    ; Extract size of frame
    mov cl,    es:[EW_RBUF_SIZE_LO]    ; Extract size of frame
    sub cx,    EW_RBUF_NHDR        ; Less the header stuff
; Set es:di to point to Ethernet type field.  es is already at base of
; page where this frame starts.  Set di after the header and two addresses.
    mov di,    EW_RBUF_NHDR+EADDR_LEN+EADDR_LEN
    push    bx            ; Save page number in bl
    push    cx            ; Save frame size
    push    es
    mov ax,    cs            ; Set ds = code
    mov ds,    ax
    assume    ds:code
    call    recv_find        ; See if type and size are wanted
    pop    ds            ; RX page pointer in ds now
    assume    ds:nothing
    pop    cx
    pop    bx
    cld            ; Copies below are forward, please
    mov ax,    es        ; Did recv_find give us a null pointer?
    or ax,    di        ; ..
    je    rcv_no_copy    ; If null, don't copy the data

    push    cx        ; We will want the count and pointer
    push    es        ;  to hand to client after copying,
    push    di        ;  so save them at this point

;; if ( (((size + 255 + EW_RBUF_NHDR) >> 8) + pg) > SM_RSTOP_PG){
    mov ax,    cx        ; Length of frame
    add ax,    EW_RBUF_NHDR+255 ; Including the overhead bytes, rounded up
    add ah,    bl        ; Compute page with last byte of data in ah
    cmp ah,    SM_RSTOP_PG    ; Over the top of the ring?
    jg    rcopy_wrap    ; Yes, move in two pieces
    mov si,    EW_RBUF_NHDR    ; One piece, starts here in first page (in ds)
    jmp    rcopy_one_piece    ; Go move it

rcopy_wrap:
;; Copy in two pieces due to buffer wraparound. */
;; n = ((SM_RSTOP_PG - pg) << 8) - EW_RBUF_NHDR;    /* To top of mem */
    mov ah,    SM_RSTOP_PG    ; Compute length of first part
    sub ah,    bl        ;  as all of the pages up to wrap point
    xor al,    al        ; 16-bit count
    sub ax,    EW_RBUF_NHDR    ; Less the four overhead bytes
    sub cx,    ax        ; Move the rest in second part
    push    cx        ; Save count of second part
    mov cx,    ax        ; Count for first move
    mov si,    EW_RBUF_NHDR    ; ds:si points at first byte to move
    shr cx,    1        ; All above are even numbers, do words.
    rep    movsw        ; Move first part of frame
    mov ax,    mem_base    ; Paragraph of base of shared memory
    mov ds,    ax        ; ..
    mov si,    SM_RSTART_PG*256  ; Offset to start of first receive page
    pop    cx        ; Bytes left to move
rcopy_one_piece:
    call    movemem
    pop    si        ; Recover pointer to destination
    pop    ds        ; Tell client it's his source
    pop    cx        ; And it's this long
    assume    ds:nothing
    call    recv_copy    ; Give it to him
rcv_no_copy:
    push    cs        ; Put ds back in code space
    pop    ds        ; ..
    assume    ds:code
    ret            ; That's it for rcv_frm


;any code after this will not be kept after initialization.
end_resident    label    byte


    public    usage_msg
usage_msg    db    "usage: WD8003E <packet_int_no> <int_level> <io_addr> <mem_base>",CR,LF,'$'

    public    copyright_msg
copyright_msg    db    "Packet driver for Western Digital WD8003E, version ",'0'+majver,".",'0'+version,CR,LF
        db    "Portions Copyright 1988, Robert C. Clements, K1BC",CR,LF,'$'

no_board_msg:
    db    "WD8003E apparently not present at this address.",CR,LF,'$'
int_no_name    db    "Interrupt number ",'$'
io_addr_name    db    "I/O port ",'$'
mem_base_name    db    "Memory address ",'$'

    extrn    set_recv_isr: near

;enter with si -> argument string, di -> word to store.
;if there is no number, don't change the number.
    extrn    get_number: near

    public    parse_args
parse_args:
    mov    di,offset int_no
    mov    bx,offset int_no_name
    call    get_number
    mov    di,offset io_addr
    mov    bx,offset io_addr_name
    call    get_number
    mov    di,offset mem_base
    mov    bx,offset mem_base_name
    call    get_number
    ret


bad_cksum:
    mov    dx,offset no_board_msg
    mov    ah,9
    int    21h
    stc
    ret


    public    etopen
etopen:                ; Initialize interface
    loadport        ; First, pulse the board reset
    setport    EW_CMD
    mov al,    EW_RESET
    out dx,    al        ; Turn on board reset bit
    xor al,    al
    out dx,    al        ; Turn off board reset bit
    setport    EW_CCMD        ; DS8390 chip's command register
    mov al,    EWC_NODMA+EWC_PAGE0
    out dx,    al        ; Switch to page zero
    setport    EW0_ISR        ; Clear all interrupt flags
    mov al,    0ffh        ; ..
    out dx,    al        ; ..
; Copy our Ethernet address from PROM into the DS8390
; (No provision in driver spec for setting a false address.)
    setport    EW_CCMD        ; Chip command register
    mov al,    EWC_NODMA+EWC_PAGE1
    out dx,    al        ; Switch to page one for writing eaddr
    mov cl,    EADDR_LEN    ; Loop for six bytes
    xor ch,    ch        ; Clear the index of bytes
    xor bx,    bx        ; Clear the addr ROM checksum
cpy_adr_loop:
    loadport        ; Base of registers
    setport    EW_SAPROM    ; Prom address
    add dl,    ch        ; Plus which byte this is
    in al,    dx        ; Get a byte of address
    add    bl,al        ; Compute the checksum
    add dl,    EW1_PHYS-EW_SAPROM ; Point at reg in chip
    out dx,    al        ; Copy that byte
    inc    ch        ; Step the index
    dec    cl        ; Count bytes
    jnz    cpy_adr_loop    ; Loop for six
    loadport        ; Get last two bytes into cksum
    setport    EW_SAPROM+EADDR_LEN
    in al,    dx        ; Get seventh byte
    add bl,    al        ; Add it in
    inc    dx        ; Step to eighth byte
    in al,    dx        ; Get last byte
    add bl,    al        ; Final checksum
    cmp bl, 0ffh        ; Correct?
    jnz    bad_cksum    ; No, board is not happy
; Clear the multicast filter enables, we don't want any of them.
    mov cl,    8        ; Eight bytes of multicast filter
    xor al,    al        ; Zeros for filter
    loadport        ; Base of multicast filter locations
    setport    EW1_MULT    ; ..
clr_mcast_l:
    out dx,    al        ; Clear a byte
    inc    dl        ; Step to next one
    dec    cl        ; Count 8 filter locs
    jnz    clr_mcast_l    ; ..
    loadport        ; Base of I/O regs
    setport    EW_CCMD        ; Chip command register
    mov al,    EWC_NODMA+EWC_PAGE0
    out dx,    al        ; Back to page zero
    setport    EW0_DCFG    ; Configure the fifo organization
    mov al,    EWDCFG_BM8    ; Fifo threshold = 8 bytes
    out dx,    al
    setport    EW0_RCNTLO    ; Clear the byte count registers
    xor al,    al        ; ..
    out dx,    al
    setport    EW0_RCNTHI
    out dx,    al        ; Clear high byte, too
    setport    EW0_RXCR    ; Set receiver to monitor mode
    mov al,    EWRXCR_MON
    out dx,    al
    setport    EW0_TXCR    ; Set transmitter mode to normal
    xor al,    al
    out dx,    al
; Turn on the shared memory block
    setport    EW_CMD        ; Point at board command register
    mov ax,    mem_base    ; Find where shared memory will be mapped
    mov al,    ah        ; Shift to right location
    sar al,    1        ;  in the map control word
    and al,    EW_MEM_MASK    ; Just these bits
    or al,    EW_MEMEN    ; Command to turn on map
    out dx,    al        ; Create that memory
; Set up control of shared memory, buffer ring, etc.
    setport    EW0_STARTPG    ; Set receiver's first buffer page
    mov al,    SM_RSTART_PG
    out dx,    al
    setport    EW0_STOPPG    ;  and receiver's last buffer page + 1
    mov al,    SM_RSTOP_PG
    out dx,    al
    setport    EW0_BOUNDARY    ; Set initial "last page we have emptied"
    mov al,    SM_RSTART_PG
    out dx,    al
    setport    EW_CCMD        ; Switch to page one registers
    mov al,    EWC_NODMA+EWC_PAGE1
    out dx,    al
    setport    EW1_CURPAG    ; Set current shared page for RX to work on
    mov al,    SM_RSTART_PG+1
    out dx,    al
    setport    EW_CCMD        ; Switch back to page zero registers
    mov al,    EWC_NODMA+EWC_PAGE0
    out dx,    al
    setport    EW0_IMR        ; Clear all interrupt enable flags
    xor al,    al
    out dx,    al
    setport    EW0_ISR        ; Clear all interrupt assertion flags
    mov al,    0ffh        ; again for safety before making the
    out dx,    al        ; interrupt be enabled
    call    set_recv_isr    ; Put ourselves in interrupt chain
    loadport
    setport    EW_CCMD        ; Now start the DS8390
    mov al,    EWC_START+EWC_NODMA
    out dx,    al        ; interrupt be enabled
    setport    EW0_RXCR    ; Tell it to accept broadcasts
    mov al,    EWRXCR_BCST
    out dx,    al
    setport    EW0_IMR        ; Tell card it can cause these interrupts
    mov al,    EWISR_ALL
    out dx,    al
    mov    dx,offset end_resident
    clc
    ret

code    ends

    end