Chip 1994 February

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Assembly Source File | 1993-06-11 | 24.7 KB | 1,067 lines

version equ 3 ;History:685,1 ; Copyright, 1991-1992, Russell Nelson, Crynwr Software ; 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. include defs.asm NI_CSR equ 0 RBI equ 2 DATA_REG equ 4 ADDR_REG equ 6 CSR0 equ 0 CSR1 equ 1 CSR2 equ 2 CSR3 equ 3 EBASE equ 0ch RBSA equ 0eh ;CSR bit definitions CSR_RBT equ 100h CSR_SHE equ 80h CSR_SWAP32 equ 40h CSR_BUF equ 20h CSR_RBE equ 10h CSR_DUM equ 08h ;for rev E. DEPCA compatability CSR_IM equ 04h CSR_IEN equ 02h CSR_LED equ 01h outport macro reg push ax setport ADDR_REG mov ax,reg out dx,ax in ax,dx ;always follow a write by a read setport DATA_REG pop ax out dx,ax in ax,dx ;always follow a write by a read endm ; ; Control and Status Register 0 (CSR0) bit definitions ; CSR0_ERR equ 8000h ; Error summary CSR0_BABL equ 4000h ; Babble transmitter timeout error CSR0_CERR equ 2000h ; Collision Error CSR0_MISS equ 1000h ; Missed packet CSR0_MERR equ 0800h ; Memory Error CSR0_RINT equ 0400h ; Reciever Interrupt CSR0_TINT equ 0200h ; Transmit Interrupt CSR0_IDON equ 0100h ; Initialization Done CSR0_INTR equ 0080h ; Interrupt Flag CSR0_INEA equ 0040h ; Interrupt Enable CSR0_RXON equ 0020h ; Receiver on CSR0_TXON equ 0010h ; Transmitter on CSR0_TDMD equ 0008h ; Transmit Demand CSR0_STOP equ 0004h ; Stop CSR0_STRT equ 0002h ; Start CSR0_INIT equ 0001h ; Initialize ; ; Initialization Block Mode operation Bit Definitions. ; M_PROM equ 8000h ; Promiscuous Mode M_INTL equ 0040h ; Internal Loopback M_DRTY equ 0020h ; Disable Retry M_COLL equ 0010h ; Force Collision M_DTCR equ 0008h ; Disable Transmit CRC) M_LOOP equ 0004h ; Loopback M_DTX equ 0002h ; Disable the Transmitter M_DRX equ 0001h ; Disable the Reciever ; ; Receive message descriptor bit definitions. ; RCV_OWN equ 8000h ; owner bit 0 = host, 1 = lance RCV_ERR equ 4000h ; Error Summary RCV_FRAM equ 2000h ; Framing Error RCV_OFLO equ 1000h ; Overflow Error RCV_CRC equ 0800h ; CRC Error RCV_BUF_ERR equ 0400h ; Buffer Error RCV_START equ 0200h ; Start of Packet RCV_END equ 0100h ; End of Packet ; ; Transmit message descriptor bit definitions. ; XMIT_OWN equ 8000h ; owner bit 0 = host, 1 = lance XMIT_ERR equ 4000h ; Error Summary XMIT_RETRY equ 1000h ; more the 1 retry needed to Xmit XMIT_1_RETRY equ 0800h ; one retry needed to Xmit XMIT_DEF equ 0400h ; Deferred XMIT_START equ 0200h ; Start of Packet XMIT_END equ 0100h ; End of Packet ; ; Miscellaneous Equates ; TRANSMIT_BUF_COUNT equ 1 ;must be a power of two. RECEIVE_BUF_COUNT equ 16 ;must be a power of two. RECEIVE_BUF_SIZE equ 1518 ; ; Receive Message Descriptor ; rcv_msg_dscp struc rmd0 dw ? ; Rec. Buffer Lo-Address rmd1 dw ? ; Status bits / Hi-Address rmd2 dw ? ; Buff Byte-length (2's Comp) rmd3 dw ? ; Receive message length rcv_msg_dscp ends ; ; Transmit Message Descriptor ; xmit_msg_dscp struc tmd0 dw ? ; Xmit Buffer Lo-Address tmd1 dw ? ; Status bits / Hi-Address tmd2 dw ? ; Buff Byte-length (2's Comp) tmd3 dw ? ; Buffer Status bits & TDR value xmit_msg_dscp ends lance_seg segment at 0 ; ;the LANCE requires that the descriptor pointers be on a qword boundary. ; align 8 transmit_dscps xmit_msg_dscp TRANSMIT_BUF_COUNT dup(<>) receive_dscps rcv_msg_dscp RECEIVE_BUF_COUNT dup(<>) ; ; LANCE Initialization Block ; align 2 init_block label byte init_mode dw 0 init_addr db EADDR_LEN dup(?) ; Our Ethernet address init_filter db 8 dup(0) ;Multicast filter. init_receive dw ?,? ;Receive Ring Pointer. init_transmit dw ?,? ;Transmit Ring Pointer. transmit_bufs equ 800h receive_bufs equ 1000h lance_seg ends code segment para public assume cs:code, ds:code public int_no int_no db 2,0,0,0 ;must be four bytes long for get_number. io_addr dw -1,-1 base_addr dw -1,-1 public driver_class, driver_type, driver_name, driver_function, parameter_list driver_class db BLUEBOOK, IEEE8023, 0 ;from the packet spec driver_type db 66 ;from the packet spec driver_name db 'DEPCA',0 ;name of the driver. driver_function db 2 ;basic, extended parameter_list label byte db 1 ;major rev of packet driver db 9 ;minor rev of packet driver db 14 ;length of parameter list db EADDR_LEN ;length of MAC-layer address dw GIANT ;MTU, including MAC headers dw MAX_MULTICAST * EADDR_LEN ;buffer size of multicast addrs dw RECEIVE_BUF_COUNT-1 ;(# of back-to-back MTU rcvs) - 1 dw TRANSMIT_BUF_COUNT-1 ;(# of successive xmits) - 1 int_num dw 0 ;Interrupt # to hook for post-EOI ;processing, 0 == none, public rcv_modes rcv_modes dw 7 ;number of receive modes in our table. dw 0 ;There is no mode zero dw 0 ;none at all. dw 0 ;only ours. dw rcv_mode_3 ;ours plus broadcast dw 0 ;some multicasts dw 0 ;all multicasts dw rcv_mode_6 ;all packets save_csr1 dw ? save_csr2 dw ? transmit_head dw transmit_dscps ;->next packet to be filled by host. receive_head dw receive_dscps ;->next packet to be filled by LANCE. ni_csr_value db CSR_SHE or CSR_DUM or CSR_IEN or CSR_SWAP32 translate_address dw ? ;->routine to translate the address. ;enter with ax = address. ;exit with di = translated address, RBI/NI_CSR set as needed. ;may trash dx. assume ds:nothing translate_64k: mov di,ax ret translate_32k: ;move the window to the appropriate address. mov di,ax loadport setport NI_CSR mov al,ni_csr_value test di,8000h je translate_32k_1 and al,not CSR_SWAP32 translate_32k_1: out dx,al and di,7fffh ;only 32K of memory. ret translate_2k: ;move the window to the appropriate address. loadport setport RBI shr ax,1 ;compute the 2K window. shr ax,1 ;divide by 8 shr ax,1 mov al,ah ;divide by 256 (8*256 = 2K). out dx,al xor di,di ret public bad_command_intercept bad_command_intercept: ;called with ah=command, unknown to the skeleton. ;exit with nc if okay, cy, dh=error if not. mov dh,BAD_COMMAND stc ret public as_send_pkt ; The Asynchronous Transmit Packet routine. ; Enter with es:di -> i/o control block, ds:si -> packet, cx = packet length, ; interrupts possibly enabled. ; Exit with nc if ok, or else cy if error, dh set to error number. ; es:di and interrupt enable flag preserved on exit. as_send_pkt: ret public drop_pkt ; Drop a packet from the queue. ; Enter with es:di -> iocb. drop_pkt: assume ds:nothing ret public xmit ; Process a transmit interrupt with the least possible latency to achieve ; back-to-back packet transmissions. ; May only use ax and dx. xmit: assume ds:nothing ret 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 cmp cx,GIANT ; Is this packet too large? ja send_pkt_toobig mov es,base_addr assume es:lance_seg xor ax,ax ;go back to base window (if changed). call translate_address xor bx,bx mov ax,18 call set_timeout send_pkt_1: test transmit_dscps[bx].tmd1,XMIT_OWN ;Did the lance chip give it back? je send_pkt_2 call do_timeout jne send_pkt_1 mov dh,CANT_SEND stc ret send_pkt_toobig: mov dh,NO_SPACE stc ret send_pkt_2: ;reset error indications. and transmit_dscps[bx].tmd1,not (XMIT_ERR or XMIT_DEF or XMIT_1_RETRY or XMIT_RETRY) ;Did the lance chip give it back? mov transmit_dscps[bx].tmd3,0 ;reset all error bits. mov ax,cx ;store the count. cmp ax,RUNT ; minimum length for Ether ja oklen mov ax,RUNT ; make sure size at least RUNT oklen: neg ax mov transmit_dscps[bx].tmd2,ax ;store the negative of the cnt. mov ax,transmit_dscps[bx].tmd0 ;store the packet. call translate_address shr cx,1 rep movsw jnc send_pkt_3 movsb send_pkt_3: xor ax,ax call translate_address mov es,base_addr assume es:lance_seg or transmit_dscps[bx].tmd1,XMIT_OWN ;give it to the lance chip. ;Inform LANCE that it should poll for a packet. loadport mov ax,CSR0_INEA or CSR0_TDMD outport CSR0 clc ret detect_board: ;test to see if a board is located at io_addr. ;setup to read first byte of ethernet address rom when successful. ;return nz if not. assume cs:code, ds:code loadport setport NI_CSR ;enable the rev. E DEPCA card. mov al,CSR_DUM out dx,al setport EBASE ;is it in this port? call detect_port je detect_board_1 ;yup! setport EBASE+1 ;look on the next port for rev. E call detect_port detect_board_1: pushf ;preserve the result. loadport setport NI_CSR ;restore the NI_CSR contents. mov al,ni_csr_value out dx,al popf ret depca_pattern db 0FFh, 00h, 55h, 0AAh, 0FFh, 00h, 55h, 0AAh detect_port: ;enter with dx = port to read from, looking for depca_pattern. ;exit with zr if we found it, nz if not. mov cx,32+8 ;do 32 reps, plus look at 8 to match. mov di,0 ;start at the beginning of the string. detect_port_1: in al,dx ;input byte. cmp al,depca_pattern[di] ;do they match? jne detect_port_2 ;no, try again. inc di ;yes, look at another character. cmp di, 8 ;need to match eight chars. jne short detect_port_3 ret detect_port_2: xor di,di ;start at the beginning of the pattern. detect_port_3: loop detect_port_1 or sp,sp ;return nz. ret public set_address set_address: ;enter with ds:si -> Ethernet address, CX = length of address. ;exit with nc if okay, or cy, dh=error if any errors. assume ds:nothing 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: mov es,base_addr mov di,offset init_addr rep movsb call initialize ;initialize with our new address. set_address_okay: mov cx,EADDR_LEN ;return their address length. clc set_address_done: movseg ds,cs assume ds:code ret rcv_mode_1: mov ax,M_DRX ;disable the receiver. jmp initialize_nomulti rcv_mode_3: xor ax,ax ;don't accept any multicast frames. call initialize_multi mov ax,0 ;non-promiscuous mode jmp short initialize_nomulti rcv_mode_5: mov ax,-1 ;accept any multicast frames. call initialize_multi mov ax,0 ;non-promiscuous mode jmp short initialize_nomulti rcv_mode_6: mov ax,M_PROM ;promiscuous mode initialize_nomulti: mov es,base_addr mov es:init_mode,ax initialize: loadport mov ax,CSR0_STOP ;reset the INIT bit. outport CSR0 mov ax,2 ;write the bus config register. outport CSR3 mov ax,save_csr1 ;write the low word. outport CSR1 mov ax,save_csr2 ;write the high word. outport CSR2 mov ax,CSR0_INEA or CSR0_STRT or CSR0_INIT ;reinit and restart. outport CSR0 setport DATA_REG mov ax,36 ;wait one second for the board call set_timeout ; to timeout. initialize_1: in ax,dx test ax,CSR0_IDON jne initialize_2 call do_timeout jne initialize_1 stc ret initialize_2: clc ret initialize_multi: ;enter with ax = value for all multicast hash bits. mov es,base_addr mov di,offset init_filter mov cx,8/2 rep stosw ret public set_multicast_list set_multicast_list: ;enter with ds:si ->list of multicast addresses, ax = number of addresses, ; cx = number of bytes. ;return nc if we set all of them, or cy,dh=error if we didn't. mov dh,NO_MULTICAST ;for some reason we can't do multi's. stc ret public terminate terminate: call rcv_mode_1 ;don't receive any packets. loadport ;disable the RAM, enable ROM. setport NI_CSR in al,dx and al,not CSR_SHE out dx,al ret public reset_interface reset_interface: ;reset the interface. assume ds:code ret ;called when we want to determine what to do with a received packet. ;enter with cx = packet length, es:di -> packet type, dl = packet class. 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 ;call this routine to schedule a subroutine that gets run after the ;recv_isr. This is done by stuffing routine's address in place ;of the recv_isr iret's address. This routine should push the flags when it ;is entered, and should jump to recv_exiting_exit to leave. ;enter with ax = address of routine to run. extrn schedule_exiting: near ;recv_exiting jumps here to exit, after pushing the flags. extrn recv_exiting_exit: near extrn count_in_err: near extrn count_out_err: near LANCE_ISR_ACKNOWLEDGE equ (CSR0_INEA or CSR0_TDMD or CSR0_STOP or CSR0_STRT or CSR0_INIT) public recv recv: ;called from the recv isr. All registers have been saved, and ds=cs. ;Upon exit, the interrupt will be acknowledged. assume ds:code xor ax,ax call translate_address loadport setport ADDR_REG mov ax,CSR0 out dx,ax in ax,dx setport DATA_REG in ax,dx mov bx,ax ;make a copy. ; Acknowledge the Interrupt from the controller, but disable further ; controller Interrupts until we service the current interrupt. ; ;(CSR0_INEA or CSR0_TDMD or CSR0_STOP or CSR0_STRT or CSR0_INIT) ; and ax,not LANCE_ISR_ACKNOWLEDGE out dx,ax in ax,dx ; follow all writes by a read test bx,CSR0_RINT ;receive interrupt? jne recv_RINT ;yes. jmp recv_done ;no, we're done. recv_RINT: mov es,base_addr assume es:lance_seg mov bx,receive_head recv_search: test lance_seg:[bx].rmd1,RCV_OWN ;do we own this buffer? je recv_own ;yes - process it. call inc_recv_ring ;go to the next one. cmp bx,receive_head ;did we get back to the beginning? jne recv_search ;not yet. jmp recv_done ;yes -- spurious interrupt! recv_own: test lance_seg:[bx].rmd1,RCV_ERR ;Any errors in this buffer? jne recv_err ;yes -- ignore this packet. mov cx,lance_seg:[bx].rmd3 and cx,0fffh ;strip off the reserved bits sub cx,4 ;leave the CRC behind. mov ax,lance_seg:[bx].rmd0 ;get the pointer into di. call translate_address push es push di push bx add di,EADDR_LEN+EADDR_LEN ;skip the ethernet addreses and ; point to the packet type. mov dl, BLUEBOOK ;assume bluebook Ethernet. mov ax, es:[di] xchg ah, al cmp ax, 1500 ja BlueBookPacket inc di ;set di to 802.2 header inc di mov dl, IEEE8023 BlueBookPacket: push cx call recv_find pop cx pop bx pop si pop ds assume ds:nothing, es:nothing mov ax,es ;is this pointer null? or ax,di je recv_free ;yes - just free the frame. push es push di push cx shr cx,1 rep movsw jnc rec_pkt_3 movsb rec_pkt_3: pop cx pop si pop ds assume ds:nothing call recv_copy jmp short recv_free recv_err: call count_in_err recv_free: xor ax,ax call translate_address movseg ds,cs assume ds:code mov es,base_addr assume es:lance_seg ;clear any error bits. and lance_seg:[bx].rmd1,not (RCV_ERR or RCV_FRAM or RCV_OFLO or RCV_CRC or RCV_BUF_ERR) or lance_seg:[bx].rmd1,RCV_OWN ;give it back to the lance. call inc_recv_ring ;go to the next one. test lance_seg:[bx].rmd1,RCV_OWN ;Do we own this one? jne recv_free_1 jmp recv_own ;yes, go parse it. recv_free_1: mov receive_head,bx ;remember where the next one starts. recv_done: loadport ;enable interrupts again. setport DATA_REG mov ax,CSR0_INEA out dx,ax ret inc_recv_ring: ;advance bx to the next receive ring descriptor. assume ds:nothing add bx,(size rcv_msg_dscp) cmp bx,offset receive_dscps + RECEIVE_BUF_COUNT * (size rcv_msg_dscp) jb inc_recv_ring_1 mov bx,offset receive_dscps inc_recv_ring_1: ret include popf.asm include timeout.asm public timer_isr timer_isr: ;if the first instruction is an iret, then the timer is not hooked iret ;any code after this will not be kept. Buffers used by the program, if any, ;are allocated from the memory between end_resident and end_free_mem. public end_resident,end_free_mem end_resident label byte end_free_mem label byte public usage_msg usage_msg db "usage: depca [options] <packet_int_no> <hardware_irq> <io_addr> <mem_addr>",CR,LF,'$' no_board_msg db "No DEPCA detected.",CR,LF,'$' io_addr_funny_msg label byte db "No DEPCA detected, continuing anyway.",CR,LF,'$' bad_reset_msg db "Unable to reset the DEPCA.",CR,LF,'$' bad_init_msg db "Unable to initialize the DEPCA.",CR,LF,'$' mem_busy_msg db "Memory already present at your chosen address.",CR,LF,'$' mem_bad_msg db "No DEPCA memory found at that memory address.",CR,LF,'$' addr_bad_msg db "Memory address should be between 0x8000 and 0xdf80 inclusive,",CR,LF db "and must be on a 2K boundary (increments of 0x80).",CR,LF,'$' public copyright_msg copyright_msg db "Packet driver for a Digital Equipment Corporation DEPCA, version ",'0'+(majver / 10),'0'+(majver mod 10),".",'0'+version,CR,LF db '$' int_no_name db "Interrupt number ",'$' io_addr_name db "I/O port ",'$' base_addr_name db "Memory address ",'$' memory_amount dw ? ;-> one of the following have_64k db "Configured for 64K of memory",CR,LF,'$' have_32k db "Configured for 32K of memory",CR,LF,'$' have_2k db "Configured for 2K of memory",CR,LF,'$' depca_signature db "DEPCA" depca_signature_len equ $-depca_signature extrn set_recv_isr: near extrn maskint: near ;enter with si -> argument string, di -> dword to store. ;if there is no number, don't change the number. extrn get_number: near ;enter with dx -> name of word, di -> dword to print. extrn print_number: near ;-> the assigned Ethernet address of the card. extrn rom_address: byte public parse_args parse_args: ;exit with nc if all went well, cy otherwise. assume ds:code mov di,offset int_no call get_number mov di,offset io_addr call get_number mov di,offset base_addr call get_number clc ret public etopen etopen: assume ds:code cmp io_addr,-1 ;Did they ask for auto-detect? je find_board call detect_board ;no, just verify its existance. je find_board_found mov dx,offset io_addr_funny_msg mov ah,9 int 21h jmp find_board_found find_board: mov io_addr,300h ;Search for the Ethernet address at 300h mov io_addr+2,0 call detect_board je find_board_found mov io_addr,200h ;Search at 200h call detect_board je find_board_found mov dx,offset no_board_msg ;Tell them that we can't find it. stc ret find_board_found: test base_addr.offs,007fh ;must be on at least a 2K boundary. jne etopen_1 test base_addr.offs,8000h ;must be in upper 512K. je etopen_1 cmp base_addr.segm,0 ;high word of segment must be zero. je etopen_2 etopen_1: mov dx,offset addr_bad_msg stc ret etopen_2: ; now we detect whether we're set to 2K, 32K, or 64K. pushf ;we're about to re-map the DEPCA cli ; memory onto somewhere illicit. ;first, we see if the ROM is mappable in and out. loadport ;disable the RAM, enable ROM. setport NI_CSR in al,dx and al,not CSR_SHE out dx,al mov bx,base_addr ;get the segment of the ROM. add bx,400h ;go up by 16K. mov translate_address,offset translate_32k mov memory_amount,offset have_32k test al,CSR_BUF ;32k or 64k mode? jne got_rom_address ;go if 32K. and ni_csr_value,not CSR_SWAP32 mov al,ni_csr_value and al,not CSR_SHE out dx,al mov translate_address,offset translate_64k mov memory_amount,offset have_64k add bx,800h ;up it by 32K more. got_rom_address: push bx mov ax,bx mov cx,4000h ;16K call memory_test pop bx jz not_rom_address ;we found RAM there... loadport setport NI_CSR in al,dx or al,CSR_SHE ;enable the RAM. out dx,al push bx mov ax,bx mov cx,4000h ;there should be 16K of RAM there. call memory_test pop bx je have_depca_mem ;there is -- we're cool. mov es,bx cmp word ptr es:[0],0aa55h ;is there a ROM there still? jne not_rom_address mov di,6 ;see if the DEPCA ROM signature is there. mov si,offset depca_signature mov cx,depca_signature_len repe cmpsb je have_depca_mem ;it is, we've got an old DEPCA. not_rom_address: ;we got here because we decided that the ROM couldn't be mapped into memory. mov translate_address,offset translate_2k mov memory_amount,offset have_2k and ni_csr_value,not CSR_SWAP32 loadport ;put our memory somewhere it can't be. setport RBSA mov ax,0f000h out dx,ax ;make sure the memory *isn't* there. mov bx,base_addr mov di,2048 / 16 call occupied_chk pushf loadport ;the memory block is empty - put our setport RBSA ; memory there. mov ax,base_addr out dx,ax popf jnc depca_mem_empty popf mov dx,offset mem_busy_msg stc ret depca_mem_empty: mov ax,base_addr ;now test our memory. mov cx,2048 call memory_test jz have_depca_mem popf ;restore the original EI. mov dx,offset mem_bad_msg stc ret have_depca_mem: popf ;restore the original EI. movseg es,cs mov di,offset rom_address mov cx,EADDR_LEN loadport ; Get our Ethernet address base. setport EBASE get_address_1: in al,dx ; get a byte of the eprom address stosb loop get_address_1 ; go back for rest mov si,offset rom_address ; copy it to the init table. mov es,base_addr mov di,offset init_addr mov cx,EADDR_LEN rep movsb mov al, int_no ; Get board's interrupt vector add al, 8 cmp al, 8+8 ; Is it a slave 8259 interrupt? jb set_int_num ; No. add al, 70h - 8 - 8 ; Map it to the real interrupt. set_int_num: xor ah, ah ; Clear high byte mov int_num, ax ; Set parameter_list int num. mov al,int_no call maskint ;disable these interrupts. loadport mov ax,CSR0_STOP ;reset the INIT bit. outport CSR0 xor ax,ax call translate_address ;set up transmit descriptor ring. mov es,base_addr assume es:lance_seg mov cx,TRANSMIT_BUF_COUNT mov bx,offset transmit_dscps mov di,offset transmit_bufs setup_transmit: call segmoffs_to_phys or dx,XMIT_START or XMIT_END mov lance_seg:[bx].tmd0,ax ;points to the buffer. mov lance_seg:[bx].tmd1,dx add bx,(size xmit_msg_dscp) add di,800h loop setup_transmit ;set up receive descriptor ring. mov cx,RECEIVE_BUF_COUNT mov bx,offset receive_dscps mov di,offset receive_bufs setup_receive: call segmoffs_to_phys or dx,RCV_OWN mov lance_seg:[bx].rmd0,ax ;points to the buffer. mov lance_seg:[bx].rmd1,dx mov lance_seg:[bx].rmd2,-RECEIVE_BUF_SIZE mov lance_seg:[bx].rmd3,0 add bx,(size rcv_msg_dscp) add di,800h loop setup_receive mov cx,RECEIVE_BUF_COUNT call compute_log2 mov di,offset receive_dscps call segmoffs_to_phys or dx,cx ;include the buffer size bits. mov init_receive[0],ax mov init_receive[2],dx mov cx,TRANSMIT_BUF_COUNT call compute_log2 mov di,offset transmit_dscps call segmoffs_to_phys or dx,cx ;include the buffer size bits. mov init_transmit[0],ax mov init_transmit[2],dx mov di,offset init_block ;now tell the board where the init call segmoffs_to_phys ; block is. mov save_csr1,ax mov save_csr2,dx call rcv_mode_3 jnc init_ok mov dx,offset bad_init_msg stc ret init_ok: ; ; Now hook in our interrupt ; call set_recv_isr loadport setport NI_CSR mov al,ni_csr_value ;disable ROM, enable rev. E DEPCA, ; enable the interrupt line, out dx,al clc ret public print_parameters print_parameters: ;echo our command-line parameters mov di,offset int_no mov dx,offset int_no_name call print_number mov di,offset io_addr mov dx,offset io_addr_name call print_number mov di,offset base_addr mov dx,offset base_addr_name call print_number mov dx,memory_amount mov ah,9 int 21h ret compute_log2: ;enter with cx = number of buffers. ;exit with cx = log2(number of buffers) << 13. mov ax,-1 compute_log2_1: inc ax shr cx,1 jne compute_log2_1 mov cl,13 shl ax,cl mov cx,ax ret segmoffs_to_phys: ;enter with es:di -> buffer. ;exit with dx:ax as the physical address of the buffer, if 0 ; The DEPCA doesn't use system memory, it uses its own. mov dx,es ;get the high 4 bits of the segment, shr dx,16-4 mov ax,es ;and the low 12 bits of the segment. shl ax,4 add ax,di ;add in the offset. adc dx,0 else xor dx,dx ;the offset is the only part of the mov ax,di ; address. endif ret include memtest.asm include occupied.asm code ends end