Atmel Avr Tcpip Atmel-crystal.asm
.include "M103def.inc"
.list
.listmac
.eseg
.db "Copyright 1998-1999 Gary T. Desrosiers. All Rights Reserved.",0
.cseg
.org 0
jmp start
;-----------------------------------------------------------------------+
; ATmega103 <===> Crystal Interconnects. |
;-----------------------------------------------------------------------+
; |
;PORTA - Unconnected. Because external SRAM enable bit set in MCUCR, |
; this port becomes the data port (AD0-7). |
; |
;PORTB - Connected to SA0-SA3 of Crystal board. PB4-PB7 is unconnected |
; |
;PORTC - Unconnected. Because external SRAM enable bit set in MCUCR, |
; this port becomes the high order address bus (A8-A15). |
; |
;PORTD - Connected to SD0-SD7 of the Crystal board (Crystal Data Bus). |
; |
;PORTE - Tied to PE0-->>/RD, PE1-->>/WR, PE2-->>/CHIPSEL, |
; and PE3<<--INTR on the Crystal board. |
; |
; Note: When using the STK300 development board, remove the PORTB, |
; PORTD, and PORTE jumpers. |
; |
;-----------------------------------------------------------------------+
; Note: When using the STK300 development board, perform the following: |
; |
; * Remove the PORTB jumpers (all 8) |
; * Remove the PORTD jumpers (all 8) |
; * Remove PORTE jumpers for RE0/RE1 |
; * Move J1 to J2 to disable 3.3v mode and enable 5.0v mode |
; * Optionally, connect the 16x1 or 2x8 LCD |
;-----------------------------------------------------------------------+
;
.equ CDB=PORTD ;Crystal Data Bus
.equ CAB=PORTB ;Crystal Address Bus
.equ CSIG=PORTE ;Crystal Signals
.equ IOR=0 ;Read
.equ IOW=1 ;Write
.equ CHIPSEL=2 ;Chip Select
.equ INTR=3 ;Interrupt signal
;
;
;
; *Change these* : Configuration equates.
;
.equ ClkFreq = 4000000 ;4 Mhz crystal
;
.equ IP1 = 192 ;first octet of IP address
.equ IP2 = 168 ;second octet of IP address
.equ IP3 = 1 ;third octet of IP address
.equ IP4 = 2 ;fourth octet of IP address
;
.equ MAC1 = 0x00 ;\
.equ MAC2 = 0x00 ; \
.equ MAC3 = 0x00 ; \
.equ MAC4 = 0x12 ; 48 bit IEEE OUI (Organizationally Unique Identifier)
.equ MAC5 = 0x34 ; /
.equ MAC6 = 0x56 ;/
;
; Some useful macros
;
.macro ppRD ;Read PacketPage port at addr @0
ldi offsetL,low(@0)
ldi offsetH,high(@0)
rcall ReadPP
.endmacro
;
.macro ppWR ;Write PacketPage port (addr,val)
ldi offsetL,low(@0)
ldi offsetH,high(@0)
ldi valueL,low(@1)
ldi valueH,high(@1)
rcall WritePP
.endmacro
;
.macro Dinput
clr wL ;Change the data bus to input
out DDRD,wL
.endmacro
;
.macro Doutput
ser wL ;Change the data bus to output
out DDRD,wL
.endmacro
;
.macro ior ;I/O port read at @0
ldi wL,@0
rcall ioRead
.endmacro
;
.macro iow ;I/O port write at @0
out CDB,wL
ldi wL,@0
out CAB,wL
rcall ioWrite
.endmacro
;
; Crystal CS8900 PacketPage equates
;
.equ portRxTxData = 0x00 ;Receive/Transmit data (port 0)
.equ portRxTxData1 = 0x02 ;Receive/Transmit data (port 0)
.equ portTxCmd = 0x04 ;Transmit Commnad
.equ portTxLength = 0x06 ;Transmit Length
.equ portISQ = 0x08 ;Interrupt status queue
.equ portPtr = 0x0a ;PacketPage pointer
.equ portData = 0x0c ;PacketPage data (port 0)
.equ portData1 = 0x0e ;PacketPage data (port 1)
;
; CS8900 PacketPage Offsets
;
.equ ppEISA = 0x0000 ;EISA Registration number of CS8900
.equ ppProdID = 0x0002 ;Product ID Number
.equ ppIOBase = 0x0020 ;I/O Base Address
.equ ppIntNum = 0x0022 ;Interrupt number (0,1,2, or 3)
.equ ppMemBase = 0x002C ;Memory Base address register (20 bit)
.equ ppRxCfg = 0x0102 ;Receiver Configuration
.equ ppRxCtl = 0x0104 ;Receiver Control
.equ ppTxCfg = 0x0106 ;Transmit Configuration
.equ ppBufCfg = 0x010A ;Buffer Configuration
.equ ppLineCtl = 0x0112 ;Line Control
.equ ppSelfCtl = 0x0114 ;Self Control
.equ ppBusCtl = 0x0116 ;Bus Control
.equ ppTestCtl = 0x0118 ;Test Control
.equ ppISQ = 0x0120 ;Interrupt status queue
.equ ppRxEvt = 0x0124 ;Receiver Event
.equ ppTxEvt = 0x0128 ;Transmitter Event
.equ ppBufEvt = 0x012C ;Buffer Event
.equ ppRxMiss = 0x0130 ;Receiver Miss Counter
.equ ppTxCol = 0x0132 ;Transmit Collision Counter
.equ ppLineSt = 0x0134 ;Line Status
.equ ppSelfSt = 0x0136 ;Self Status
.equ ppBusSt = 0x0138 ;Bus Status
.equ ppTxCmd = 0x0144 ;Transmit Command Request
.equ ppTxLength = 0x0146 ;Transmit Length
.equ ppIndAddr = 0x0158 ;Individual Address (IA)
.equ ppRxStat = 0x0400 ;Receive Status
.equ ppRxLength = 0x0402 ;Receive Length
.equ ppRxFrame = 0x0404 ;Receive Frame Location
.equ ppTxFrame = 0x0A00 ;Transmit Frame Location
;
; Register Numbers
;
.equ REG_NUM_MASK = 0x003F
.equ REG_NUM_RX_EVENT = 0x0004
.equ REG_NUM_TX_EVENT = 0x0008
.equ REG_NUM_BUF_EVENT = 0x000C
.equ REG_NUM_RX_MISS = 0x0010
.equ REG_NUM_TX_COL = 0x0012
;
; Self Control Register
;
.equ SELF_CTL_RESET = 0x0040
.equ SELF_CTL_HC1E = 0x2000
.equ SELF_CTL_HCB1 = 0x8000
;
; Self Status Register
;
.equ SELF_ST_INIT_DONE = 0x0080
.equ SELF_ST_SI_BUSY = 0x0100
.equ SELF_ST_EEP_PRES = 0x0200
.equ SELF_ST_EEP_OK = 0x0400
.equ SELF_ST_EL_PRES = 0x0800
;
; Bus Control Register
;
.equ BUS_CTL_USE_SA = 0x0200
.equ BUS_CTL_MEM_MODE = 0x0400
.equ BUS_CTL_IOCHRDY = 0x1000
.equ BUS_CTL_INT_ENBL = 0x8000
;
; Bus Status Register
;
.equ BUS_ST_TX_BID_ERR = 0x0080
.equ BUS_ST_RDY4TXNOW = 0x0100
;
; Line Control Register
;
.equ LINE_CTL_RX_ON = 0x0040
.equ LINE_CTL_TX_ON = 0x0080
.equ LINE_CTL_AUI_ONLY = 0x0100
.equ LINE_CTL_10BASET = 0x0000
;
; Test Control Register
;
.equ TEST_CTL_DIS_LT = 0x0080
.equ TEST_CTL_ENDEC_LP = 0x0200
.equ TEST_CTL_AUI_LOOP = 0x0400
.equ TEST_CTL_DIS_BKOFF = 0x0800
.equ TEST_CTL_FDX = 0x4000
;
; Receiver Configuration Register
;
.equ RX_CFG_SKIP = 0x0040
.equ RX_CFG_RX_OK_IE = 0x0100
.equ RX_CFG_CRC_ERR_IE = 0x1000
.equ RX_CFG_RUNT_IE = 0x2000
.equ RX_CFG_X_DATA_IE = 0x4000
;
; Receiver Event Register
;
.equ RX_EVENT_RX_OK = 0x0100
.equ RX_EVENT_IND_ADDR = 0x0400
.equ RX_EVENT_BCAST = 0x0800
.equ RX_EVENT_CRC_ERR = 0x1000
.equ RX_EVENT_RUNT = 0x2000
.equ RX_EVENT_X_DATA = 0x4000
;
;Receiver Control Register
;
.equ RX_CTL_RX_OK_A = 0x0100
.equ RX_CTL_MCAST_A = 0x0200
.equ RX_CTL_IND_A = 0x0400
.equ RX_CTL_BCAST_A = 0x0800
.equ RX_CTL_CRC_ERR_A = 0x1000
.equ RX_CTL_RUNT_A = 0x2000
.equ RX_CTL_X_DATA_A = 0x4000
;
;Transmit Configuration Register
;
.equ TX_CFG_LOSS_CRS_IE = 0x0040
.equ TX_CFG_SQE_ERR_IE = 0x0080
.equ TX_CFG_TX_OK_IE = 0x0100
.equ TX_CFG_OUT_WIN_IE = 0x0200
.equ TX_CFG_JABBER_IE = 0x0400
.equ TX_CFG_16_COLL_IE = 0x8000
.equ TX_CFG_ALL_IE = 0x8FC0
;
;Transmit Event Register
;
.equ TX_EVENT_TX_OK = 0x0100
.equ TX_EVENT_OUT_WIN = 0x0200
.equ TX_EVENT_JABBER = 0x0400
.equ TX_EVENT_16_COLL = 0x1000
;
; Transmit Command Register
;
.equ TX_CMD_START_5 = 0x0000
.equ TX_CMD_START_381 = 0x0080
.equ TX_CMD_START_1021 = 0x0040
.equ TX_CMD_START_ALL = 0x00C0
.equ TX_CMD_FORCE = 0x0100
.equ TX_CMD_ONE_COLL = 0x0200
.equ TX_CMD_NO_CRC = 0x1000
.equ TX_CMD_NO_PAD = 0x2000
;
;Buffer Configuration Register
;
.equ BUF_CFG_SW_INT = 0x0040
.equ BUF_CFG_RDY4TX_IE = 0x0100
.equ BUF_CFG_TX_UNDR_IE = 0x0200
;
;
; Register file assignments
;
.def count=r14
.def lcdPos=r15
.def wL=r16
.def wH=r17
.def offsetL=r18
.def offsetH=r19
.def valueL=r20
.def valueH=r21
.def tempL=r22
.def tempH=r23
.def flags=r24
.def scratch=r25
.def lengthL=r26
.def lengthH=r27
.def chksumL=r0
.def chksumM=r1
.def chksumH=r2
;
; start of packet data in sram
;
.equ packet = 0x60
;
; Packet offset equates
;
;
; Packet header
;
.equ pktLenH = 0x00
.equ pktLenL = 0x01
.equ pktDest0H= 0x02
.equ pktDest0L= 0x03
.equ pktDest1H= 0x04
.equ pktDest1L= 0x05
.equ pktDest2H= 0x06
.equ pktDest2L= 0x07
.equ pktSrc0H = 0x08
.equ pktSrc0L = 0x09
.equ pktSrc1H = 0x0a
.equ pktSrc1L = 0x0b
.equ pktSrc2H = 0x0c
.equ pktSrc2L = 0x0d
.equ pktTypeH = 0x0e
.equ pktTypeL = 0x0f
;
; ARP
;
.equ ar_hwtype= 0x10 ;hardware type
.equ ar_prtype= 0x12 ;protocol type
.equ ar_hwlen = 0x14 ;hardware address length
.equ ar_prlen = 0x15 ;protocol address length
.equ ar_op = 0x16 ;ARP operation (1=request, 2=reply)
.equ ar_sha = 0x18 ;senders hardware address
.equ ar_spa = 0x1e ;senders IP address
.equ ar_tha = 0x22 ;target hardware address
.equ ar_tpa = 0x28 ;target IP address
;
; IP header
;
.equ ip_verlen= 0x10 ;IP version and header length(in longs)
.equ ip_tos = 0x11 ;IP type of service
.equ ip_len = 0x12 ;packet length (length-header_length)
.equ ip_id = 0x14 ;datagram id
.equ ip_fragoff= 0x16 ;fragment offset
.equ ip_ttl = 0x18 ;time to live (in gateway hops)
.equ ip_proto = 0x19 ;protocol (ICMP=1, TCP=6, EGP=8, UDP=17)
.equ ip_cksum = 0x1a ;header checksum
.equ ip_src = 0x1c ;IP address of source
.equ ip_dst = 0x20 ;IP addess of destination
.equ ip_data = 0x24
;
; IP value equates
;
.equ IPT_ICMP = 1 ;protocol type for ICMP packets
.equ IPT_TCP = 6 ;protocol type for TCP packets
.equ IPT_EGP = 8 ;protocol type for EGP packets
.equ IPT_UDP = 0x11 ;protocol type for UDP packets
;
; ICMP header
;
.equ ic_type = ip_data ;0=reply, 8=request, others=who-cares
.equ ic_code = ic_type+1 ;code
.equ ic_cksum = ic_code+1 ;checksum of header+data
.equ ic_id = ic_cksum+2 ;message id
.equ ic_seq = ic_id+2 ;sequence number
;
; UDP Header
;
.equ u_src = ip_data ;source udp port number
.equ u_dst = u_src+2 ;destination UDP port number
.equ u_len = u_dst+2 ;length of UDP header+data
.equ u_cksum = u_len+2 ;checksum (see note)
.equ u_data = u_cksum+2 ;start of data
;
; Note: checksum is calculated by taking the 16 bit sums of the ip_src, ip_dst,
; ip_proto, u_len, and the sum starting at u_src for a length of u_len
; yes, this means that u_len is taken twice! u_cksum is zero during the calc.
; The sum is then one's complemented. This is the checksum
;
;
start:
ldi wL,low(RAMEND)
out SPL,wL
ldi wL,high(RAMEND) ;setup the stack
out SPH,wL
ldi wL,$c0 ;Setup for external
out MCUCR,wL ; SRAM Enable and Wait State Enable
ldi wL,0b11110111 ;PORTE INTR signal input all others output
out DDRE,wL
sbi CSIG,IOR ;no read
sbi CSIG,IOW ;no write
sbi CSIG,CHIPSEL ;don't select chip
ser wL
out DDRB,wL ;PORTB (Crystal Address Bus) output
clr count ;packet counter
Dinput
ldi scratch,255 ;wait
rcall wait
rcall lcd_reset ;reset LCD
rcall VerChip ;make sure that the CS8900 is connected, Z set if true
ldi wL,'>' ;success indicator
breq VerOK
ldi wL,'<' ;failure indicator on LCD
VerOK: rcall lcd_write
rcall ResetChip ;reset CS8900
rcall InitChip ;initialize CS8900
;
; We already did this in VerChip but get the signature bytes for the CS8900 and display
; them on the LCD. Should be 3000 630E 0500
;
Dinput
ior portPtr+1 ;read PacketPage Ptr for high order byte
mov valueH,wL ;save high low
ior portPtr ;read PacketPage Ptr for high order byte
mov valueL,wL ;save high low
rcall outHL
ppRD ppEISA ;get the EISA number whoch should be 0x630E
rcall outHL
ppRD ppProdID ;get the Product ID which should be 000x xxxx 0000 0000
rcall outHL
clr flags ;Packet flags
loop:
sbis PINE,INTR ;wait for interrupt
rjmp loop
rcall ProcessISQ ;process the queue
sbrs flags,0 ;received frame flag
rjmp loop
cbr flags,1 ;clear the receive flag
;
; We're going to display on the LCD, t: CC LLLL FFFF
; Where t=r for recieved frame, a=arp request, p=ping request
; CC=count of frames received so far
; LLLL=length of this frame
; FFFF=frame type. For example 0800 for IP, 0806 for ARP
;
rcall lcd_clear
clr lcdPos
inc lcdPos ;start in second LCD position
ldi wL,':'
rcall lcd_write
mov wL,count
rcall toHexH
rcall lcd_write
mov wL,count ;display the count of received frames
rcall toHexL
rcall lcd_write
ldi wL,' '
rcall lcd_write
lds valueH,packet+pktLenH ;display the packet length
lds valueL,packet+pktLenL
rcall outHL
lds valueH,packet+pktTypeH ;and the packet type
lds valueL,packet+pktTypeL
rcall outHL
sbrc flags,1 ;bit set when valid arp
rjmp ArpRequest
sbrc flags,2 ;bit set when valid UDP Request on port 7
rjmp UDP7Request
sbrc flags,3 ;bit set when valid ICMP Ping request received
rjmp PingRequest
clr lcdPos
ldi wL,'r'
rcall lcd_write
rjmp loop
ArpRequest:
cbr flags,2 ;clear the valid arp request flag
clr lcdPos
ldi wL,'a'
rcall lcd_write
rcall WriteARP ;respond to the ARP request with our IP/MAC
rjmp loop
PingRequest:
cbr flags,8 ;clear the valid ICMP ping request flag
clr lcdPos
ldi wL,'p'
rcall lcd_write
rcall WritePing ;respond to the ping
rjmp loop
UDP7Request:
cbr flags,4 ;clear the valid UDP port 7 request flag
clr lcdPos
ldi wL,'u'
rcall lcd_write
rcall WriteUDP ;echo reply
rjmp loop
;
; Converts the valueH/valueL to hex and displays it on the LCD
;
outHL:
mov wL,valueH
rcall toHexH
rcall lcd_write
mov wL,valueH
rcall toHexL
rcall lcd_write
mov wL,valueL
rcall toHexH
rcall lcd_write
mov wL,valueL
rcall toHexL
rcall lcd_write
ldi wL,' '
rcall lcd_write
ret
toHexL:
andi wL,0x0f
ori wL,0x30
cpi wL,0x3a
brlo thlX
ldi wH,7
add wL,wH
thlX: ret
toHexH:
lsr wL
lsr wL
lsr wL
lsr wL
ori wL,0x30
cpi wL,0x3a
brlo thhX
ldi wH,7
add wL,wH
thhX: ret
;
; Send the reset sequence to the LCD's HD44780 controller.
;
lcd_reset:
ldi scratch,20 ;wait 20 milliseconds
rcall wait
ldi wL,$30 ;Spec said to send this init sequence
sts $8000,wL
ldi scratch,4
rcall wait ;Wait 4ms
ldi wL,$30 ;Spec said to send this init sequence
sts $8000,wL ;Send init sequence again
rcall delay100us ;Wait 100us
ldi wL,$30 ;Spec said to send this init sequence
sts $8000,wL ;and one last time
rcall delay100us ;Wait 100us
ldi wL,$3F ;Display off
sts $8000,wL
ldi scratch,4
rcall wait ;Wait 4ms
ldi wL,$0F ;Display on
sts $8000,wL
ldi scratch,4
rcall wait ;Wait 4ms
ldi wL,$06 ;Entry Mode Set
sts $8000,wL
ldi scratch,4
rcall wait ;Wait 4ms
rcall lcd_clear ;clear display
clr lcdPos ;position of character on LCD
ret
;
; Clear the LCD display
;
lcd_clear:
ldi wL,$01 ;Clear Display
sts $8000,wL
ldi scratch,4
rcall wait ;Wait 4ms
clr lcdPos ;position of character on LCD
ret
;
; Sends the character in r16 to the LCD. The register "lcdPos" is
; incremented to the next position. The register value is a modulous 8
; and the LCD is broken into two sections (as is typical for HD44780 based LCDs),
; position 0-7 on LCD1 and 0-7 on LCD2.
;
lcd_write:
mov r17,lcdPos
sbrs r17,3
rjmp lcd_1
andi r17,0x07
ori r17,0x40
rjmp lcd_2
lcd_1: andi r17,0x07
lcd_2: ori r17,0x80
sts $8000,r17
rcall delay40us
sts $C000,r16
rcall delay40us
inc lcdPos
ret
delay40us:
push wL
ldi wL,$40
loop3: dec wL
brne loop3
pop wL
ret
delay100us:
push wL
ldi wL,$88
loop4: dec wL
brne loop4
pop wL
ret
;
; wait for W milliseconds
;
;delay the given number of milliseconds using a software loop
; Enter: scratch = number of milliseconds to delay
; Exit: scratch,wL,wH = undefined
wait:
wait1: ldi wH,high((ClkFreq / 1000) / 4)
ldi wL,low((ClkFreq / 1000) / 4)
wait2: subi wL,1 ;(1)
sbci wH,0 ;(1)
brne wait2 ;(2)
dec scratch
brne wait1
ret
;************************************************************************
;* C S 8 9 0 0 D r i v e r F u n c t i o n s *
;************************************************************************
;
; WriteARP - Send a response ARP to the requestor
;
WriteARP:
ldi zL,low(packet)
ldi zH,high(packet) ;load the z reg with the packet address
clr wL
st z,wL
ldi wL,42 ;length of ARP response frame
std z+2,wL
; Target HW address MAC (6)
lds wL,packet+pktSrc0H
sts packet+ar_tha,wL
sts packet+pktDest0H,wL
lds wL,packet+pktSrc0L
sts packet+ar_tha+1,wL
sts packet+pktDest0L,wL
lds wL,packet+pktSrc1H
sts packet+ar_tha+2,wL
sts packet+pktDest1H,wL
lds wL,packet+pktSrc1L
sts packet+ar_tha+3,wL
sts packet+pktDest1L,wL
lds wL,packet+pktSrc2H
sts packet+ar_tha+4,wL
sts packet+pktDest2H,wL
lds wL,packet+pktSrc2L
sts packet+ar_tha+5,wL
sts packet+pktDest2L,wL
; Target IP (4)
lds wL,packet+ar_spa
sts packet+ar_tpa,wL
lds wL,packet+ar_spa+1
sts packet+ar_tpa+1,wL
lds wL,packet+ar_spa+2
sts packet+ar_tpa+2,wL
lds wL,packet+ar_spa+3
sts packet+ar_tpa+3,wL
; Senders IP (4)
ldi wL,IP1
sts packet+ar_spa,wL
ldi wL,IP2
sts packet+ar_spa+1,wL
ldi wL,IP3
sts packet+ar_spa+2,wL
ldi wL,IP4
sts packet+ar_spa+3,wL
; Src HW Address MAC (6)
ldi wL,MAC1
sts packet+ar_sha,wL
sts packet+pktSrc0H,wL
ldi wL,MAC2
sts packet+ar_sha+1,wL
sts packet+pktSrc0L,wL
ldi wL,MAC3
sts packet+ar_sha+2,wL
sts packet+pktSrc1H,wL
ldi wL,MAC4
sts packet+ar_sha+3,wL
sts packet+pktSrc1L,wL
ldi wL,MAC5
sts packet+ar_sha+4,wL
sts packet+pktSrc2H,wL
ldi wL,MAC6
sts packet+ar_sha+5,wL
sts packet+pktSrc2L,wL
; Packet type (2)
ldi wL,0x08
sts packet+pktTypeH,wL
ldi wL,0x06
sts packet+pktTypeL,wL
; Hardware type (2)
ldi wL,0x00
sts packet+ar_hwtype,wL
ldi wL,0x01
sts packet+ar_hwtype+1,wL
; Protocol type (2)
ldi wL,0x08
sts packet+ar_prtype,wL
ldi wL,0x00
sts packet+ar_prtype+1,wL
; Hardware and protocol address lengths (2)
ldi wL,0x06
sts packet+ar_hwlen,wL
ldi wL,0x04
sts packet+ar_prlen,wL
; Operation (response) (2)
ldi wL,0x00
sts packet+ar_op,wL
ldi wL,0x02
sts packet+ar_op+1,wL
rcall WritePacket
ret
;
; WriteUDP - Send a response to the port 7 UDP echo request
;
WriteUDP:
clr wL
sts packet+ip_cksum,wL ;clear
sts packet+ip_cksum+1,wL ; checksum
lds wL,packet+ip_src ;move
sts packet+ip_dst,wL ; ip
lds wL,packet+ip_src+1 ; of
sts packet+ip_dst+1,wL ; source
lds wL,packet+ip_src+2 ; to
sts packet+ip_dst+2,wL ; dest
lds wL,packet+ip_src+3
sts packet+ip_dst+3,wL
ldi wL,IP1 ;move
sts packet+ip_src,wL ; our
ldi wL,IP2 ; ip
sts packet+ip_src+1,wL ; address
ldi wL,IP3 ; to
sts packet+ip_src+2,wL ; source
ldi wL,IP4
sts packet+ip_src+3,wL
lds wL,packet+pktSrc0H ;move
sts packet+pktDest0H,wL ; mac src to dest
lds wL,packet+pktSrc0L
sts packet+pktDest0L,wL
lds wL,packet+pktSrc1H ;move
sts packet+pktDest1H,wL ; mac src to dest
lds wL,packet+pktSrc1L
sts packet+pktDest1L,wL
lds wL,packet+pktSrc2H ;move
sts packet+pktDest2H,wL ; mac src to dest
lds wL,packet+pktSrc2L
sts packet+pktDest2L,wL
ldi wL,MAC1 ;move
sts packet+pktSrc0H,wL ; our
ldi wL,MAC2 ; MAC
sts packet+pktSrc0L,wL ; address
ldi wL,MAC3 ; to
sts packet+pktSrc1H,wL ; source
ldi wL,MAC4
sts packet+pktSrc1L,wL
ldi wL,MAC5
sts packet+pktSrc2H,wL
ldi wL,MAC6
sts packet+pktSrc2L,wL
ldi lengthL,20 ;length of IP header
clr lengthH
ldi zL,low(packet+ip_verlen)
ldi zH,high(packet+ip_verlen)
rcall cksum
sts packet+ip_cksum,valueH ;save new IP checksum
sts packet+ip_cksum+1,valueL
lds wH,packet+u_src ;get src port
lds wL,packet+u_dst ;put dest port
sts packet+u_src,wL ;in source
sts packet+u_dst,wH ;put source port in dest
lds wH,packet+u_src+1 ;get src port
lds wL,packet+u_dst+1 ;put dest port
sts packet+u_src+1,wL ;in source
sts packet+u_dst+1,wH ;put source port in dest
clr wL
sts packet+u_cksum,wL ;clear UDP checksum for new calc
sts packet+u_cksum+1,wL ;clear byte two
ldi zl,low(packet+ip_src)
ldi zh,high(packet+ip_src)
lds lengthH,packet+ip_len
lds lengthL,packet+ip_len+1
ldi wL,20-8 ;ip_len-20+8 (20 is the length of an IP header.
clr wH ; 8 is the length of the two IP fields (ip_src/ip_dst)
sub lengthL,wL
sbc lengthH,wH
rcall cksum
clr wH
lds wL,packet+ip_proto ;get protocol (1 byte)
sub valueL,wL ;add to accum
sbc valueH,wH
lds wH,packet+u_len ;add in UDP len
lds wL,packet+u_len+1
sub valueL,wL
sbc valueH,wH
sts packet+u_cksum,valueH
sts packet+u_cksum+1,valueL
rcall WritePacket
ret
;
; WritePing - Send a ICMP Ping response
;
WritePing:
;we might want to check in the future for IA or broadcast requests
clr wL
sts packet+ip_cksum,wL
sts packet+ip_cksum+1,wL ;clear checksum
lds wL,packet+ip_src ;move
sts packet+ip_dst,wL ; ip
lds wL,packet+ip_src+1 ; of
sts packet+ip_dst+1,wL ; source
lds wL,packet+ip_src+2 ; to
sts packet+ip_dst+2,wL ; dest
lds wL,packet+ip_src+3
sts packet+ip_dst+3,wL
ldi wL,IP1 ;move
sts packet+ip_src,wL ; our
ldi wL,IP2 ; ip
sts packet+ip_src+1,wL ; address
ldi wL,IP3 ; to
sts packet+ip_src+2,wL ; source
ldi wL,IP4
sts packet+ip_src+3,wL
clr wL
sts packet+ic_cksum,wL ;clear ICMP
sts packet+ic_cksum+1,wL ; checksum
sts packet+ic_type,wL ;make type a reply
sts packet+ic_code,wL ;clear code
lds wL,packet+pktSrc0H ;move
sts packet+pktDest0H,wL ; mac src to dest
lds wL,packet+pktSrc0L
sts packet+pktDest0L,wL
lds wL,packet+pktSrc1H ;move
sts packet+pktDest1H,wL ; mac src to dest
lds wL,packet+pktSrc1L
sts packet+pktDest1L,wL
lds wL,packet+pktSrc2H ;move
sts packet+pktDest2H,wL ; mac src to dest
lds wL,packet+pktSrc2L
sts packet+pktDest2L,wL
ldi wL,MAC1 ;move
sts packet+pktSrc0H,wL ; our
ldi wL,MAC2 ; MAC
sts packet+pktSrc0L,wL ; address
ldi wL,MAC3 ; to
sts packet+pktSrc1H,wL ; source
ldi wL,MAC4
sts packet+pktSrc1L,wL
ldi wL,MAC5
sts packet+pktSrc2H,wL
ldi wL,MAC6
sts packet+pktSrc2L,wL
ldi lengthL,20 ;set length of
clr lengthH ; checksum calculation = length of IP header
ldi zL,low(packet+ip_verlen);displacement to start of IP header
ldi zH,high(packet+ip_verlen)
rcall cksum ;calculate the checksum
sts packet+ip_cksum,valueH ;set new checksum
sts packet+ip_cksum+1,valueL
lds lengthH,packet+ip_len ;get length high
lds lengthL,packet+ip_len+1 ;calc length of ICMP header+data
subi lengthL,20 ;-length of IP header
sbci lengthH,0
ldi zL,low(packet+ic_type) ;start of ICMP header
ldi zH,high(packet+ic_type) ;start of ICMP header
rcall cksum
sts packet+ic_cksum,valueH ;set new checksum
sts packet+ic_cksum+1,valueL
rcall WritePacket
ICMPDone:
ret
;----------------------------------------------------------------------
; Receive Event
; Input with RxEvent in valueH
;
ReceiveEvent:
;
; It's important to read the status and length high-order
; byte first.
;
Dinput ;make data bus input
ior portRxTxData+1 ;read and discard status
ior portRxTxData ;read and discard status
ldi yL,low(packet) ;set indirect
ldi yH,high(packet)
ior portRxTxData+1 ;get length high
st y+,wL ;save in header
mov lengthH,wL ; and in lengthH
ior portRxTxData ;get length low
st y+,wL ;save in header area
mov lengthL,wL ; and in lengthL
sbrc lengthL,0 ;odd length?
adiw lengthL,1 ;yes, increment lengthL/lengthH by 1
lsr lengthH ;divide high by 2 and set carry appropriately
ror lengthL ;rotate carry into lower and divide by 2
ReadFrame:
ior portRxTxData ;read from CS8900
st y+,wL ;write it to sram
ior portRxTxData+1 ;read from CS8900
st y+,wL ;write it to sram
sbiw lengthL,1 ;decrement lengthL/lengthH
brpl ReadFrame
inc count ;increment packet counter
sbr flags,1 ;flag frame read
lds wL,packet+pktTypeH ;check if packet type
cpi wL,0x08 ; is 0x0806 (ARP)
brne ChkIP
lds wL,packet+pktTypeL
cpi wL,0x06
breq DoArp
ChkIP:
lds wL,packet+pktTypeH ;check if packet type
cpi wL,0x08 ; is 0x0806 (ARP)
brne REReturn
lds wL,packet+pktTypeL
cpi wL,0x00
breq DoIP
REReturn:
ret
;
; It's an arp request, Could be a request or a response.
; ARP packets are small so the whole thing is always in
; the register file.
;
DoArp:
lds wL,packet+ar_hwtype+1 ;make sure it's 1
cpi wL,0x01
brne DoArpX
lds wL,packet+ar_prtype ;compare to high
cpi wL,0x08 ;make sure it's 0x0800
brne DoArpX
lds wL,packet+ar_prtype+1 ;compare to high
cpi wL,0x00 ;make sure it's 0x0800
brne DoArpX
lds wL,packet+ar_hwlen ;make sure it's 6 for hwlen
cpi wL,0x06 ;compare to high
brne DoArpX
lds wL,packet+ar_prlen ;make sure it's 4 for protocol length
cpi wL,0x04 ;compare to low
brne DoArpX
lds wL,packet+ar_op+1 ;make sure it's 0x0001 for arp request
cpi wL,0x01 ;compare to low
brne DoArpX
lds wL,packet+ar_tpa
cpi wL,IP1
brne DoArpX
lds wL,packet+ar_tpa+1
cpi wL,IP2
brne DoArpX
lds wL,packet+ar_tpa+2
cpi wL,IP3
brne DoArpX
lds wL,packet+ar_tpa+3
cpi wL,IP4
brne DoArpX
; If we got to here, then we have a valid ARP request for our IP address
sbr flags,2 ;set ARP flag
DoArpX:
ret
;
; Process IP packet for ICMP or UDP requests
;
DoIP:
lds wL,packet+ip_proto ;compare to this packet's proto
cpi wL,IPT_ICMP ; to ICMP?
breq DoICMP ;go process the ICMP packet
cpi wL,IPT_UDP ; to UDP?
breq DoUDP ;go process the UDP packet
ret ;just return, we dont process this type
;
; Process UDP Port 7 echo requests
;
DoUDP:
lds wL,packet+u_dst+1 ;compare to UDP packet
cpi wL,7 ;port we're listing for requests on
brne DoUDPDone
sbr flags,4 ;we have a request for our port 7
DoUDPDone:
ret
;
; Process ICMP (ping) requests
;
DoICMP:
sbr flags,8 ;set flag to indicate ICMP ping request
ret
;
; Calc checksum. Reads packet at offset zL/zH for
; lengthH/lengthL bytes and calculates the checksum
; in valueH/valueL.
;
cksum: clr chksumL ;we do the arithmetic
clr chksumM ; using a 24
clr chksumH ; bit area
sbrs lengthL,0 ;odd length?
rjmp cksumC
mov yL,zL
mov yH,zH
add yL,lengthL
adc yH,lengthH
clr wL
st y,wL ;clear byte after last
adiw lengthL,1
cksumC: lsr lengthH
ror lengthL
cksuml: ld wH,z+ ;get high byte of 16-bit word
ld wL,z+
add chksumL,wL ;add to accum
brcc noLcarry
ldi wL,1
add chksumM,wL
brcc noLcarry
add chksumH,wL
noLcarry:
add chksumM,wH ;add in the high byte
brcc noHcarry
inc chksumH
noHcarry:
subi lengthL,1
sbci lengthH,0
clr wL
cpi lengthL,0
cpc lengthH,wL
breq CkDone
brpl cksuml
CkDone: add chksumL,chksumH ;add in the third byte of 24 bit area
brcc CkDone1
inc chksumM
CkDone1:mov valueL,chksumL
com valueL
mov valueH,chksumM
com valueH
ret
;
; Transmit Event
;
TransmitEvent:
ret
;
; Processes the pending interrupt requests from the Interrupt Status Queue
;
ProcessISQ:
; Read the ISQ
NextEvt:
Dinput
ior portISQ ;read interrupt status queue
mov valueL,wL ;save value low
ior portISQ+1 ;read interrupt status queue high
mov valueH,wL ;save value high
tst valueL ;get val
breq EvtRet
cpi valueL,REG_NUM_RX_EVENT
breq evtRecv
cpi valueL,REG_NUM_TX_EVENT
breq evtTran ;Ingore BufEvent, RxMiss, and TxCol
rjmp NextEvt
evtRecv:
rcall ReceiveEvent
rjmp NextEvt
evtTran:
rcall TransmitEvent
rjmp NextEvt
EvtRet: ret
;
; Initializes the chip
;
InitChip:
ppWR ppLineCtl,LINE_CTL_10BASET ;set to 10BaseT
ppWR ppTestCtl,TEST_CTL_FDX ;set to full duplex
ppWR ppRxCfg,RX_CFG_RX_OK_IE ;enable RxOK interrupt
ppWR ppRxCtl,(RX_CTL_RX_OK_A|RX_CTL_IND_A|RX_CTL_BCAST_A)
ppWR ppTxCfg,TX_CFG_ALL_IE
;
; Important: The IA needs to be byte revered IA=aa:bb:cc:dd:ee:ff
;
ppWR ppIndAddr,(MAC2<<8|MAC1) ;0xbbaa Write
ppWR ppIndAddr+2,(MAC4<<8|MAC3) ;0xddcc out
ppWR ppIndAddr+4,(MAC6<<8|MAC5) ;0xffee 48 bit IA
ppWR ppIntNum,0x00 ;INT is on INTRQ0
ppRD ppBusCtl ;get Bus Control
sbr valueH,0x80 ;enable irq
rcall WritePP
ppRD ppLineCtl ;get Line Control
sbr valueL,0xc0 ;set SerRxOn and SerTxOn
rcall WritePP
ret
;
; Resets the CS8900
;
ResetChip:
ppWR ppSelfCtl,SELF_CTL_RESET ;issue a reset to the chip
ResetWait:
ldi scratch,1 ;wait for
rcall wait ;a millisecond
ppRD ppSelfCtl ;get the Self Control status
sbrc valueL,6 ;see it bit 6 (RESET) was cleared
rjmp ResetWait ;no, then still in reset, wait some more
ppRD ppSelfSt ;get self status
sbrs valueL,7 ;bit 7 is INITD
rjmp ResetWait ; when set, initialization of the CS8900 is done
ret
;
; Verifies that the CS8900 is attached and sets the STATUS,Z flag to
; indicate success or not set if failure.
;
VerChip:
Dinput ;make the data bus input
; first, get the signature at portPtr which should be 0x3000
ior portPtr ;read PacketPage Ptr
mov valueL,wL ;save value low
ior portPtr+1 ;read PacketPage Ptr for high order byte
mov valueH,wL ;save high low
tst valueL ;should be 0 (i.e. 0x3000 low is 0x00)
brne VerBad
cpi valueH,0x30 ;high part of 0x3000
brne VerBad
ppRD ppEISA ;get the EISA number whoch should be 0x630E
cpi valueL,0x0e
brne VerBad
cpi valueH,0x63
brne VerBad
ppRD ppProdID ;get the Product ID which should be 000x xxxx 0000 0000
;where x xxxx = 0 0011 for rev E and 0 0101 for rev F
tst valueL ;set return status
VerBad: ret ;return with Z indicating success or not.
;
; Writes the packet for lengthL/lengthH
;
WritePacket:
Doutput
ldi wL,TX_CMD_START_ALL
iow portTxCmd
clr wL
iow portTxCmd+1
lds wL,packet+pktLenL ;length
iow portTxLength ; of packet
lds wL,packet+pktLenH ; to send
iow portTxLength+1
WPGetStat:
ppRD ppBusSt ;get BusStatus
sbrs valueH,0 ;is BUS_ST_RDY4TXNOW (ready for transmit)
rjmp WPGetStat ;no, wait for it
Doutput
ldi zL,low(packet+pktDest0H)
ldi zH,high(packet+pktDest0H)
lds lengthH,packet+pktLenH
lds lengthL,packet+pktLenL
sbrs lengthL,0 ;odd length?
rjmp PacketEven ;nope, continue
adiw lengthL,1 ;increment length
PacketEven:
lsr lengthH ;divide high by 2 and set carry appropriately
ror lengthL ;rotate carry into lower and divide by 2
PacketWriteLoop:
ld wL,z+ ;get next byte
iow portRxTxData
ld wL,z+ ;get next byte
iow portRxTxData+1
sbiw lengthL,1 ;decrement lengthL/lengthH
brpl PacketWriteLoop
ret
;
; Writes the value at valueH/valueL to the PagePacket register who's
; address is in offsetH/offsetL
;
WritePP:
Doutput ;make the data bus output
mov wL,offsetL ;get the low order byte
iow portPtr ;write to PacketPage Ptr
mov wL,offsetH ;get the high order byte
iow portPtr+1 ;write to PacketPage ptr
mov wL,valueL ;get low order value to write
iow portData ;write to PacketPage data
mov wL,valueH ;get high order data
iow portData+1 ;write to PacketPage data
ret
;
; Reads the PagePacket at offsetH/offsetL and returns the result in
; valueH/valueL.
;
ReadPP:
Doutput ;make the data bus output
mov wL,offsetL ;get the offset to read
iow portPtr ;write to PacketPage Ptr
mov wL,offsetH ;get the high order offset
iow portPtr+1 ;PagePacket Pointer Register high byte
Dinput ;make the data bus input
ior portData ;read the PacketPage data
mov valueL,wL ;save value low
ior portData+1 ;read the high order byte
mov valueH,wL ;save the high order byte value
ret
ioRead:
out CAB,wL
cbi CSIG,CHIPSEL
cbi CSIG,IOR
nop
nop
in wL,PIND
sbi CSIG,IOR
sbi CSIG,CHIPSEL
ret
;
ioWrite:
cbi CSIG,CHIPSEL
cbi CSIG,IOW
nop
sbi CSIG,IOW
sbi CSIG,CHIPSEL
ret
| file: /Techref/atmel/avr/tcpip/atmel-crystal.asm, 43KB, , updated: 1999/6/4 13:02, local time: 2025/5/2 20:29,
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