'-----------------------------------------------------------
' Atmega168 and ENC28J60
'-----------------------------------------------------------
' Version 1.0 - june 2007 by Ben Zijlstra
' august 2007 addins by Viktor Varga

'fusebits:
'Atmega168 - External clock (from 6.25 Mhz to 12.5 Mhz) No div by 8

$regfile = "m168def.dat"
$crystal = 12500000
$baud = 19200                                               'put terminal on 19200 baud

$hwstack = 100
$swstack = 100
$framesize = 100

$include "enc28j60.inc"

$lib "tcpip.lbx"
$lib "datetime.lbx"

Enc28j60_cs Alias Portb.2
Led Alias Portb.1

'/* Maximum frame length - The Atmega168 has only 1024 byte internal RAM! */
Const Max_framelen = 500                                    '500 byte will be enough for common tasks

Config Enc28j60_cs = Output
Config Led = Output
Config Date = Dmy , Separator = -
Set Led                                                     'Turn off the tuxgraphics board LED

Dim X As Word
Dim A(5) As Byte
Dim Bank As Byte
Dim Enc28j60_data As Byte
Dim Nextpacketptr As Word
Dim Value As Byte
Dim Wdata As Word
Dim Buffer(max_framelen) As Byte
Dim Length As Word
Dim Rxstat As Word
Dim Ip_id As Word
Dim I_header_length As Word
Dim Msg_temp As String * 55

'Ethernet packet destination
Dim T_enetpacketdest0 As Byte At Buffer Overlay
Dim T_enetpacketdest1 As Byte At Buffer + &H01 Overlay
Dim T_enetpacketdest2 As Byte At Buffer + &H02 Overlay
Dim T_enetpacketdest3 As Byte At Buffer + &H03 Overlay
Dim T_enetpacketdest4 As Byte At Buffer + &H04 Overlay
Dim T_enetpacketdest5 As Byte At Buffer + &H05 Overlay
'Ethernet packet source
Dim T_enetpacketsrc0 As Byte At Buffer + &H06 Overlay
Dim T_enetpacketsrc1 As Byte At Buffer + &H07 Overlay
Dim T_enetpacketsrc2 As Byte At Buffer + &H08 Overlay
Dim T_enetpacketsrc3 As Byte At Buffer + &H09 Overlay
Dim T_enetpacketsrc4 As Byte At Buffer + &H0A Overlay
Dim T_enetpacketsrc5 As Byte At Buffer + &H0B Overlay
'Ethernet packet type
Dim T_enetpackettype As Word At Buffer + &H0C Overlay
Dim T_arp_hwtype1 As Byte At Buffer + &H0F Overlay
'Arp
Dim T_arp_prttype1 As Byte At Buffer + &H11 Overlay
Dim T_arp_hwlen As Byte At Buffer + &H12 Overlay
Dim T_arp_prlen As Byte At Buffer + &H13 Overlay
Dim T_arp_op1 As Byte At Buffer + &H15 Overlay
'arp source ip address
Dim T_arp_sipaddr0 As Byte At Buffer + &H1C Overlay
Dim T_arp_sipaddr1 As Byte At Buffer + &H1D Overlay
Dim T_arp_sipaddr2 As Byte At Buffer + &H1E Overlay
Dim T_arp_sipaddr3 As Byte At Buffer + &H1F Overlay
'arp target IP address
Dim T_arp_tipaddr0 As Byte At Buffer + &H26 Overlay
Dim T_arp_tipaddr1 As Byte At Buffer + &H27 Overlay
Dim T_arp_tipaddr2 As Byte At Buffer + &H28 Overlay
Dim T_arp_tipaddr3 As Byte At Buffer + &H29 Overlay
Dim T_arp_tipaddr As Long At Buffer + &H26 Overlay
'IP header layout IP version and header length
Dim T_ip_vers_len As Byte At Buffer + &H0E Overlay
Dim T_arp_hwtype0 As Byte At Buffer + &H0E Overlay
'Arp
Dim T_arp_prttype0 As Byte At Buffer + &H10 Overlay
Dim T_arp_op0 As Byte At Buffer + &H14 Overlay
'arp source mac address
Dim T_arp_src_enetpacket0 As Byte At Buffer + &H16 Overlay
Dim T_arp_src_enetpacket1 As Byte At Buffer + &H17 Overlay
Dim T_arp_src_enetpacket2 As Byte At Buffer + &H18 Overlay
Dim T_arp_src_enetpacket3 As Byte At Buffer + &H19 Overlay
Dim T_arp_src_enetpacket4 As Byte At Buffer + &H1A Overlay
Dim T_arp_src_enetpacket5 As Byte At Buffer + &H1B Overlay
'arp source mac address
Dim T_arp_dest_enetpacket0 As Byte At Buffer + &H20 Overlay
Dim T_arp_dest_enetpacket1 As Byte At Buffer + &H21 Overlay
Dim T_arp_dest_enetpacket2 As Byte At Buffer + &H22 Overlay
Dim T_arp_dest_enetpacket3 As Byte At Buffer + &H23 Overlay
Dim T_arp_dest_enetpacket4 As Byte At Buffer + &H24 Overlay
Dim T_arp_dest_enetpacket5 As Byte At Buffer + &H25 Overlay
Dim T_tos As Byte At Buffer + &H0F Overlay

'Buffer length
Dim T_ip_pktlen0 As Byte At Buffer + &H10 Overlay
Dim T_ip_pktlen1 As Byte At Buffer + &H11 Overlay

Dim T_id0 As Byte At Buffer + &H12 Overlay
Dim T_id1 As Byte At Buffer + &H13 Overlay
Dim T_flags As Byte At Buffer + &H14 Overlay
Dim T_offset As Byte At Buffer + &H15 Overlay
Dim T_ttl As Byte At Buffer + &H16 Overlay
'protocol (ICMP=1, TCP=6, UDP=11)
Dim T_ip_proto As Byte At Buffer + &H17 Overlay
'header checksum
Dim T_ip_hdr_cksum0 As Byte At Buffer + &H18 Overlay
Dim T_ip_hdr_cksum1 As Byte At Buffer + &H19 Overlay
Dim T_ip_hdr_cksum As Word At Buffer + &H18 Overlay
'IP address of source
Dim T_ip_srcaddr0 As Byte At Buffer + &H1A Overlay
Dim T_ip_srcaddr1 As Byte At Buffer + &H1B Overlay
Dim T_ip_srcaddr2 As Byte At Buffer + &H1C Overlay
Dim T_ip_srcaddr3 As Byte At Buffer + &H1D Overlay
Dim T_ip_srcaddr As Long At Buffer + &H1A Overlay
'IP address of destination
Dim T_ip_destaddr0 As Byte At Buffer + &H1E Overlay
Dim T_ip_destaddr1 As Byte At Buffer + &H1F Overlay
Dim T_ip_destaddr2 As Byte At Buffer + &H20 Overlay
Dim T_ip_destaddr3 As Byte At Buffer + &H21 Overlay
Dim T_ip_destaddr As Long At Buffer + &H1E Overlay
Dim T_icmp_type As Byte At Buffer + &H22 Overlay
Dim T_icmp_code As Byte At Buffer + &H23 Overlay
Dim T_icmp_cksum0 As Byte At Buffer + &H24 Overlay
Dim T_icmp_cksum1 As Byte At Buffer + &H25 Overlay
Dim T_icmp_cksum As Word At Buffer + &H24 Overlay
Dim Tcp_srcporth As Byte At Buffer + &H22 Overlay
Dim Tcp_srcportl As Byte At Buffer + &H23 Overlay
Dim Tcp_destporth As Byte At Buffer + &H24 Overlay
Dim Tcp_destportl As Byte At Buffer + &H25 Overlay
Dim Tcp_seqnum3 As Byte At Buffer + &H26 Overlay
Dim Tcp_seqnum2 As Byte At Buffer + &H27 Overlay
Dim Tcp_seqnum1 As Byte At Buffer + &H28 Overlay
Dim Tcp_seqnum0 As Byte At Buffer + &H29 Overlay
Dim Tcp_acknum3 As Byte At Buffer + &H2A Overlay
Dim Tcp_acknum2 As Byte At Buffer + &H2B Overlay
Dim Tcp_acknum1 As Byte At Buffer + &H2C Overlay
Dim Tcp_acknum0 As Byte At Buffer + &H2D Overlay
'Dim Tcp_hdr As Byte At Buffer + &H2E Overlay
Dim Tcp_flags As Byte At Buffer + &H2F Overlay
Dim Tcp_cksumh As Byte At Buffer + &H32 Overlay
Dim Tcp_cksuml As Byte At Buffer + &H33 Overlay
Dim Tcp_cksum As Word At Buffer + &H32 Overlay
'UDP header
Dim T_udp_srcport0 As Byte At Buffer + &H22 Overlay
Dim T_udp_srcport1 As Byte At Buffer + &H23 Overlay
Dim T_udp_srcport As Word At Buffer + &H22 Overlay
Dim T_udp_destport0 As Byte At Buffer + &H24 Overlay
Dim T_udp_destport1 As Byte At Buffer + &H25 Overlay
Dim T_udp_destport As Word At Buffer + &H24 Overlay
Dim T_udp_len0 As Byte At Buffer + &H26 Overlay
Dim T_udp_len1 As Byte At Buffer + &H27 Overlay
Dim T_udp_chksum0 As Byte At Buffer + &H28 Overlay
Dim T_udp_chksum1 As Byte At Buffer + &H29 Overlay
Dim T_udp_chksum As Word At Buffer + &H28 Overlay
Dim T_udp_data As Byte At Buffer + &H2A Overlay
Dim T_udp_data1 As Byte At Buffer + &H2B Overlay
Dim T_udp_data2 As Byte At Buffer + &H2C Overlay
Dim T_udp_data3 As Byte At Buffer + &H2D Overlay
Dim T_udp_data4 As Byte At Buffer + &H2E Overlay
Dim T_udp_data5 As Byte At Buffer + &H2F Overlay
Dim T_udp_data6 As Byte At Buffer + &H30 Overlay
Dim T_udp_data7 As Byte At Buffer + &H31 Overlay
Dim T_udp_data8 As Byte At Buffer + &H32 Overlay
Dim T_udp_data9 As Byte At Buffer + &H33 Overlay
Dim T_udp_data10 As Byte At Buffer + &H34 Overlay
Dim T_udp_data11 As Byte At Buffer + &H35 Overlay
Dim T_udp_data12 As Byte At Buffer + &H36 Overlay
Dim T_udp_data13 As Byte At Buffer + &H37 Overlay
Dim T_udp_data14 As Byte At Buffer + &H38 Overlay
Dim T_udp_data15 As Byte At Buffer + &H39 Overlay
Dim T_udp_data16 As Byte At Buffer + &H3A Overlay
Dim T_udp_data17 As Byte At Buffer + &H3B Overlay
Dim T_udp_data18 As Byte At Buffer + &H3C Overlay
Dim T_udp_data19 As Byte At Buffer + &H3D Overlay
Dim T_udp_data20 As Byte At Buffer + &H3E Overlay
Dim T_udp_data21 As Byte At Buffer + &H3F Overlay
Dim T_udp_data22 As Byte At Buffer + &H40 Overlay
Dim T_udp_data23 As Byte At Buffer + &H41 Overlay
Dim T_udp_data24 As Byte At Buffer + &H42 Overlay
Dim T_udp_data25 As Byte At Buffer + &H43 Overlay
Dim T_udp_data26 As Byte At Buffer + &H44 Overlay
Dim T_udp_data27 As Byte At Buffer + &H45 Overlay
Dim T_udp_data28 As Byte At Buffer + &H46 Overlay
Dim T_udp_data29 As Byte At Buffer + &H47 Overlay
Dim T_udp_data30 As Byte At Buffer + &H48 Overlay
Dim T_udp_data31 As Byte At Buffer + &H49 Overlay
Dim T_udp_data32 As Byte At Buffer + &H4A Overlay

Dim I_chksum32 As Long
Dim I_checksum16 As Word
Dim T_ip_pktlen As Word
Dim Result16 As Word
Dim Result16h As Byte At Result16 + 1 Overlay
Dim Result16l As Byte At Result16 Overlay
Dim I_value16 As Word
Dim I_value16h As Byte At I_value16 + 1 Overlay
Dim I_value16l As Byte At I_value16 Overlay
Dim Hulp2 As Word
Dim Work As Byte

'variables with overlays
Dim Myip(4) As Byte
Dim My_ip As Long At Myip Overlay
Dim Mymac(6) As Byte

Dim Incoming_ack As Long
Dim Incoming_ack0 As Byte At Incoming_ack Overlay
Dim Incoming_ack1 As Byte At Incoming_ack + 1 Overlay
Dim Incoming_ack2 As Byte At Incoming_ack + 2 Overlay
Dim Incoming_ack3 As Byte At Incoming_ack + 3 Overlay

'for NTP-routine
Dim S(4) As Byte
Dim L1 As Long At S Overlay                                 ' Overlay a long variable to receive-string
' with overlay you need no transfer from the byte-array to a long-variable
Dim L2 As Long

'toegevoegd voor TCP
Dim Tcp_fin As Bit
Dim Tcp_syn As Bit
Dim Tcp_rst As Bit
Dim Tcp_psh As Bit
Dim Tcp_ack As Bit
Dim Tcp_urg As Bit
Dim Tcpdatalen_in As Word
Dim Flags As Byte

Dim Client_seqnum As Long
Dim Client_seqnum0 As Byte At Client_seqnum Overlay
Dim Client_seqnum1 As Byte At Client_seqnum + 1 Overlay
Dim Client_seqnum2 As Byte At Client_seqnum + 2 Overlay
Dim Client_seqnum3 As Byte At Client_seqnum + 3 Overlay

Dim Tempword As Word
Dim Tempwordh As Byte At Tempword + 1 Overlay
Dim Tempwordl As Byte At Tempword Overlay

Dim Val1 As Word
Dim Val2 As Word
Dim Y As Word

Const Synflag = 0
Const Finflag = 1

Declare Sub Enc28j60init
Declare Sub Enc28j60readcontrolregbyte(byval Register As Byte)
Declare Sub Enc28j60writecontrolregbyte(byval Register As Byte , Byval Value As Byte)
Declare Sub Enc28j60selectbank(byval Bank As Byte)
Declare Sub Enc28j60bitfield_set(byval Register As Byte , Byval Value As Byte)
Declare Sub Enc28j60bitfield_clear(byval Register As Byte , Byval Value As Byte)
Declare Sub Enc28j60readphyword(byval Phyregister As Byte)
Declare Sub Enc28j60writephyword(byval Phyregister As Byte , Byval Wdata As Word)
Declare Sub Enc28j60packetsend(byval Pcktlen As Word)
Declare Sub Enc28j60packetreceive
Declare Sub Enc28j60poll
Declare Sub Arpreply
Declare Sub Pingreply
Declare Sub Setip_id
Declare Sub Udp_receive
Declare Sub Udp_checksum
Declare Sub Setipaddrs
Declare Sub Tcp
Declare Sub Echopacket
Declare Sub Ip_header_checksum
Declare Sub Icmp_checksum
Declare Sub Ntp_get
Declare Sub Ntp
Declare Sub Http
Declare Sub Tcp_checksum
Declare Sub Src2dest
Declare Sub Inc2seq
Declare Sub Seq2ack
Declare Sub Ack2inc
Declare Sub Src2mymac
Declare Sub Srcdestchksum


'MAC address
Mymac(1) = &H43
Mymac(2) = &HC6
Mymac(3) = &HB3
Mymac(4) = &HF3
Mymac(5) = &HAB
Mymac(6) = &H9E


'IP address
Myip(1) = 192
Myip(2) = 168
Myip(3) = 0
Myip(4) = 61

'Configuration of the SPI-bus
Config Spi = Hard , Interrupt = Off , Data Order = Msb , Master = Yes , Polarity = Low , Phase = 0 , Clockrate = 4 , Noss = 0

'init the spi pins
Spiinit

Enc28j60_cs = 0
'reset ENC28J60
X = Enc28j60_soft_reset
Spiout X , 1
Enc28j60_cs = 1
Do
Call Enc28j60readcontrolregbyte(estat)
X = Enc28j60_data.estat_clkrdy
Loop Until X = 1

'clock from default divide/4 (6.25 Mhz) to divide/2 (12.5 Mhz)
Call Enc28j60writecontrolregbyte(ecocon , &B00000010)
Waitms 250
Print
Print "Starting Tux"

Call Enc28j60selectbank(3)
'EREVID
A(1) = &B000_10010
Enc28j60_cs = 0
Spiout A(1) , 1
Spiin A(1) , 2
Print "Enc28j60-version = " ; A(2)
Enc28j60_cs = 1

Call Enc28j60init
Call Ntp_get                                                'get the Network Time once

Do
   Call Enc28j60poll
Loop

End

Sub Enc28j60init
   'do bank 0 stuff
   'initialize receive buffer
   '16-bit transfers, must write low byte first
   'set receive buffer start address
   Nextpacketptr = Rxstart_init
   Value = Low(rxstart_init)
   Call Enc28j60writecontrolregbyte(erxstl , Value)
   Value = High(rxstart_init)
    Call Enc28j60writecontrolregbyte(erxsth , Value)
    'set receive pointer address
    Value = Low(rxstart_init)
    Call Enc28j60writecontrolregbyte(erxrdptl , Value)
    Value = High(rxstart_init)
    Call Enc28j60writecontrolregbyte(erxrdpth , Value)
    'set receive buffer end
    Value = Low(rxstop_init)
    Call Enc28j60writecontrolregbyte(erxndl , Value)
    Value = High(rxstop_init)
    Call Enc28j60writecontrolregbyte(erxndh , Value)
    'set transmit buffer start
    Value = Low(txstart_init)
    Call Enc28j60writecontrolregbyte(etxstl , Value)
    Value = High(txstart_init)
    Call Enc28j60writecontrolregbyte(etxsth , Value)
    'do bank 2 stuff
    'enable MAC receive
    Value = 0
    Value.macon1_marxen = 1
    Value.macon1_txpaus = 1
    Value.macon1_rxpaus = 1
    Call Enc28j60writecontrolregbyte(macon1 , Value)
    'bring MAC out of reset
    'enable automatic padding and CRC operations
    Value = 0
    Value.macon3_padcfg0 = 1
    Value.macon3_txcrcen = 1
    Value.macon3_frmlnen = 1
    Call Enc28j60writecontrolregbyte(macon3 , Value)
    'set inter-frame gap (non-back-to-back)
    Call Enc28j60writecontrolregbyte(maipgl , &H12)
    Call Enc28j60writecontrolregbyte(maipgh , &H0C)
    'set inter-frame gap (back-to-back)
    Call Enc28j60writecontrolregbyte(mabbipg , &H12)
    'set the maximum packet size which the controller will accept
    Value = Low(max_framelen)
    Call Enc28j60writecontrolregbyte(mamxfll , Value)
    Value = High(max_framelen)
    Call Enc28j60writecontrolregbyte(mamxflh , Value)

    'bank 3 stuff
    Call Enc28j60writecontrolregbyte(maadr5 , Mymac(1))
    Call Enc28j60writecontrolregbyte(maadr4 , Mymac(2))
    Call Enc28j60writecontrolregbyte(maadr3 , Mymac(3))
    Call Enc28j60writecontrolregbyte(maadr2 , Mymac(4))
    Call Enc28j60writecontrolregbyte(maadr1 , Mymac(5))
    Call Enc28j60writecontrolregbyte(maadr0 , Mymac(6))
    'no loopback of transmitted frames
    Call Enc28j60writephyword(phcon2 , Phcon2_hdldis)
    'switch to bank 0
    Call Enc28j60selectbank(0)
    'enable interrupts
    Value = 0
    Value.eie_intie = 1
    Value.eie_pktie = 1
    Call Enc28j60bitfield_set(eie , Value)

    'filters according to Guido
    Call Enc28j60writecontrolregbyte(epmm0 , &H3F)
    Call Enc28j60writecontrolregbyte(epmm1 , &H30)
    Call Enc28j60writecontrolregbyte(epmcsl , &HF9)
    Call Enc28j60writecontrolregbyte(epmcsh , &HF7)

    Value = 0
    Value.erxfcon_pmen = 1                                  'Pattern Match enable (ARP only)
    Value.erxfcon_ucen = 1                                  'Unicast enable
    Call Enc28j60bitfield_set(erxfcon , Value)

    Value = 0
    Value.erxfcon_bcen = 1                                  'Broadcast disable
    Call Enc28j60bitfield_clear(erxfcon , Value)
    'CRC check is enabled by default

    'Something is wrong with the Broadcast filter (or the whole theory), it seems
    'like every packet is coming in

    'enable packet reception
    Value = 0
    Value.econ1_rxen = 1
    Call Enc28j60bitfield_set(econ1 , Value)

    'Reset transmit logic
    Value = 0
    Value.econ1_txrst = 1
    Call Enc28j60bitfield_set(econ1 , Value)
    Call Enc28j60bitfield_clear(econ1 , Value)
 End Sub


Sub Enc28j60selectbank(bank As Byte)
   'get ECON1 (BSEL1 en BSEL0)
   A(1) = &B000_11111
   Enc28j60_cs = 0
   Spiout A(1) , 1
   Spiin A(1) , 2
   Enc28j60_cs = 1
   A(2) = A(2) And &B1111_1100                              'strip bank part
   A(2) = A(2) Or Bank
   A(1) = &B010_11111
   Enc28j60_cs = 0
   Spiout A(1) , 2
   Enc28j60_cs = 1
End Sub


Sub Enc28j60writecontrolregbyte(register As Byte , Value As Byte)
   Bank = 0
   If Register.7 = 1 Then Bank = 2
   If Register.6 = 1 Then Bank = Bank + 1
   Register = Register And &B00011111
   Call Enc28j60selectbank(bank)
   Register.6 = 1                                           'to get a 010_register
   A(1) = Register
   A(2) = Value
   Enc28j60_cs = 0
   Spiout A(1) , 2
   Enc28j60_cs = 1
End Sub


Sub Enc28j60readcontrolregbyte(register As Byte)
   Local Mcphy As Byte
   Bank = 0
   Mcphy = 0
   If Register.7 = 1 Then Bank = 2
   If Register.6 = 1 Then Bank = Bank + 1
   If Register.5 = 1 Then Mcphy = 1
   Register = Register And &B00011111
   Call Enc28j60selectbank(bank)
   A(1) = Register
   Enc28j60_cs = 0
   Spiout A(1) , 1
   Spiin A(1) , 3
   Enc28j60_cs = 1
   'Depending of register (E, MAC, MII) yes or no dummybyte
   If Mcphy = 1 Then
      Enc28j60_data = A(2)
      Else
      Enc28j60_data = A(3)
   End If
End Sub


Sub Enc28j60bitfield_set(register As Byte , Value As Byte)
   Bank = 0
   If Register.7 = 1 Then Bank = 2
   If Register.6 = 1 Then Bank = Bank + 1
   Register = Register And &B00011111
   Call Enc28j60selectbank(bank)
   Register = Register Or &B100_00000
   A(1) = Register
   A(2) = Value
   Enc28j60_cs = 0
   Spiout A(1) , 2
   Enc28j60_cs = 1
End Sub


Sub Enc28j60bitfield_clear(register As Byte , Value As Byte)
   Bank = 0
   If Register.7 = 1 Then Bank = 2
   If Register.6 = 1 Then Bank = Bank + 1
   Register = Register And &B00011111
   Call Enc28j60selectbank(bank)
   Register = Register Or &B101_00000
   A(1) = Register
   A(2) = Value
   Enc28j60_cs = 0
   Spiout A(1) , 2
   Enc28j60_cs = 1
End Sub


Sub Enc28j60readphyword(phyregister As Byte)
   'set the right address and start the register read operation
   Call Enc28j60writecontrolregbyte(miregadr , Phyregister)
   Call Enc28j60writecontrolregbyte(micmd , Micmd_miird)
   'wait until the PHY read complets
   Do
   Call Enc28j60readcontrolregbyte(mistat)
   Loop Until Enc28j60_data.mistat_busy = 0
   'quit reading
   Call Enc28j60writecontrolregbyte(micmd , 0)
   'get data value
   Call Enc28j60readcontrolregbyte(mirdl)
   Wdata = Enc28j60_data
   Shift Wdata , Left , 8
   Call Enc28j60readcontrolregbyte(mirdh)
   Wdata = Wdata + Enc28j60_data
End Sub


Sub Enc28j60writephyword(phyregister As Byte , Wdata As Word)
   Call Enc28j60readphyword(phyregister)
   Local Temp As Byte
   'set the PHY register address
   Call Enc28j60writecontrolregbyte(miregadr , Phyregister)
   Call Enc28j60readcontrolregbyte(miregadr)
   Temp = Miregadr
   Value = Low(wdata)
   Call Enc28j60writecontrolregbyte(miwrl , Value)
   Value = High(wdata)
   Call Enc28j60writecontrolregbyte(miwrh , Value)
   Do
   Call Enc28j60readcontrolregbyte(mistat)
   Loop Until Enc28j60_data.mistat_busy = 0
End Sub


Sub Enc28j60poll
   Call Enc28j60readcontrolregbyte(epktcnt)
   If Enc28j60_data > 0 Then
      Call Enc28j60packetreceive
   End If
End Sub


Sub Enc28j60packetreceive
   Reset Led
   Local Wtemp As Word
   'set the read pointer to the start of the received packet
   Value = Low(nextpacketptr)
   Call Enc28j60writecontrolregbyte(erdptl , Value)
   Value = High(nextpacketptr)
   Call Enc28j60writecontrolregbyte(erdpth , Value)
    Enc28j60_cs = 0
    'Send Read Buffer Memory command
    Spdr = &H3A
    Do
    Loop Until Spsr.spif = 1
    'Get the first 6 byte (3 word: Nextpacketptr, Packetlength, Rxstat)
    For X = 1 To 6
          Spdr = &HFF                                       'SPI read
          Do
          Loop Until Spsr.spif = 1                          'SPI ready
          Buffer(x) = Spdr
    Next X
    Nextpacketptr = Buffer(2) * 256
    Nextpacketptr = Nextpacketptr + Buffer(1)
    Length = Buffer(4) * 256
    Length = Length + Buffer(3)
    Rxstat = Buffer(6) * 256
    Rxstat = Rxstat + Buffer(5)
    'Get the payload
    Length = Length - 4                                     'Discard CRC
    For X = 1 To Length
          Spdr = &HFF                                       'SPI read
          Do
          Loop Until Spsr.spif = 1                          'SPI ready
          Buffer(x) = Spdr
    Next X
    Enc28j60_cs = 1
   'move the rx read pointer to the start of the next received packet
   'this frees the memory we just read out
   Value = Low(nextpacketptr)
   Call Enc28j60writecontrolregbyte(erxrdptl , Value)
   Value = High(nextpacketptr)
   Call Enc28j60writecontrolregbyte(erxrdpth , Value)
   'decrement the packet counter indicate we are done with this packet
   Value = 0
   Value.econ2_pktdec = 1
   Call Enc28j60bitfield_set(econ2 , Value)
   Set Led


    'Handle the packet
    If Buffer(13) = &H08 Then
      If Buffer(14) = &H06 Then                             'Type:ARP
         If Buffer(21) = &H00 Then                          'ARP request
            If Buffer(22) = &H01 Then                       'ARP request
              If Buffer(39) = Myip(1) Then                  'ARP for us
                If Buffer(40) = Myip(2) Then
                   If Buffer(41) = Myip(3) Then
                      If Buffer(42) = Myip(4) Then
                        Call Arpreply
                      End If
                   End If
                End If
              End If
            End If
         End If
      End If
      If Buffer(14) = &H00 Then                             'Type:IP
         If Buffer(15) = &H45 Then                          'We handle only simple IP packets
            'If Buffer(21) = 0 Then                          'We handle only non fragmented packets
              If Buffer(31) = Myip(1) Then                  'Ip packet for us
                If Buffer(32) = Myip(2) Then
                   If Buffer(33) = Myip(3) Then
                      If Buffer(34) = Myip(4) Then
                        If Buffer(24) = 1 Then              'Protocol:ICMP
                           If Buffer(35) = &H08 Then        'ICMP echo request
                              Call Pingreply
                           End If
                        End If
                        If Buffer(24) = 17 Then             'Protocol:UDP
                           Call Udp_receive
                        End If
                        If Buffer(24) = 6 Then              'Protocol:TCP
                           Call Tcp
                        End If
                      End If
                   End If
                End If
              'End If
            End If
         End If
      End If
    End If
End Sub


Sub Enc28j60packetsend(pcktlen As Word)
   'Load packet into the ENC
   Enc28j60_cs = 0
   Spdr = Enc28j60_write_buf_mem
   Do
   Loop Until Spsr.spif = 1
   Spdr = &B000_1110                                        'per packet byte
   Do
   Loop Until Spsr.spif = 1
   For X = 1 To Pcktlen
      Spdr = Buffer(x)
      Do
      Loop Until Spsr.spif = 1
   Next X
   Enc28j60_cs = 1
   'Minimum packet length is 60
   If Pcktlen < 60 Then Pcktlen = 60
   'Reset transmit logic
   Value = 0
   Value.econ1_txrst = 1
   Call Enc28j60bitfield_set(econ1 , Value)
   Call Enc28j60bitfield_clear(econ1 , Value)
   'set the write pointer to start of transmit buffer area
   Value = Low(txstart_init)
   Call Enc28j60writecontrolregbyte(ewrptl , Value)
   Value = High(txstart_init)
   Call Enc28j60writecontrolregbyte(ewrpth , Value)
   'set the TXND pointer to correspond to the packet size given
   Value = Low(txstart_init)
   Value = Value + Low(pcktlen)
   Call Enc28j60writecontrolregbyte(etxndl , Value)
   Value = High(txstart_init)
   Value = Value + High(pcktlen)
   Call Enc28j60writecontrolregbyte(etxndh , Value)
   'write per-packet control byte has been put in the writeroutine
   'send the contents of the transmit buffer onto the network
   Value = 0
   Value.econ1_txrts = 1
   Call Enc28j60bitfield_set(econ1 , Value)
End Sub


Sub Arpreply
   'The original request packet is in the buffer, we just change some things
   'Swap MAC addresses
   Call Src2dest
   'Set source MAC in ethernet frame, pos 7
   Call Src2mymac
   'Copy target MAC in ARP packet
   T_arp_dest_enetpacket0 = T_enetpacketdest0
   T_arp_dest_enetpacket1 = T_enetpacketdest1
   T_arp_dest_enetpacket2 = T_enetpacketdest2
   T_arp_dest_enetpacket3 = T_enetpacketdest3
   T_arp_dest_enetpacket4 = T_enetpacketdest4
   T_arp_dest_enetpacket5 = T_enetpacketdest5
   'Set target IP in ARP packet
   T_arp_tipaddr0 = T_arp_sipaddr0
   T_arp_tipaddr1 = T_arp_sipaddr1
   T_arp_tipaddr2 = T_arp_sipaddr2
   T_arp_tipaddr3 = T_arp_sipaddr3
   'Copy source MAC to ARP
   T_arp_src_enetpacket0 = T_enetpacketsrc0
   T_arp_src_enetpacket1 = T_enetpacketsrc1
   T_arp_src_enetpacket2 = T_enetpacketsrc2
   T_arp_src_enetpacket3 = T_enetpacketsrc3
   T_arp_src_enetpacket4 = T_enetpacketsrc4
   T_arp_src_enetpacket5 = T_enetpacketsrc5
   'Set source IP to ARP packet pos 29
   T_arp_sipaddr0 = Myip(1)
   T_arp_sipaddr1 = Myip(2)
   T_arp_sipaddr2 = Myip(3)
   T_arp_sipaddr3 = Myip(4)
   'Set ARP type from Request to Reply
   T_arp_op1 = 2
   'Send the reply packet
   Call Enc28j60packetsend(42)
End Sub


Sub Pingreply
   Local Packetlength As Word
   Packetlength = Buffer(17) * 256
   Packetlength = Packetlength + Buffer(18)
   Packetlength = Packetlength + 13                         'We are going to calculate the checksum till the end of packet (IP length + 14 byte of the ethernet stuff), -1 to get word start
   'set echo reply
   T_icmp_type = &H00
   T_icmp_code = &H00
   'setup the IP-header
   Call Setipaddrs
   Call Icmp_checksum
   Packetlength = Packetlength + 1
   'Send the reply packet
   Call Enc28j60packetsend(packetlength)
End Sub


Sub Setip_id
   Buffer(19) = High(ip_id)
   Buffer(20) = Low(ip_id)
   Ip_id = Ip_id + 1
End Sub


' Routine to handle UDP-traffic
'
Sub Udp_receive
   Local Udp_port As Word
   Local Udp_porth As Byte
   Local Udp_portl As Byte

   Udp_porth = &H88
   Udp_portl = &H13

   Udp_port = Udp_porth
   Shift Udp_port , Left , 8
   Udp_port = Udp_port + Udp_portl

   'From within a VB-program
   'non-echo on PORT 5000
   If T_udp_destport = Udp_port Then
            If T_udp_srcport = &H2500 Then                  ' &h0025 NTP protocol
               Call Ntp
               Exit Sub
            End If

         Select Case T_udp_data
               Case &H00 : Print "Action A"
               Case &H01 : Print "Action B"
               Case &H02 : Print "Action C"
               Case &H03 : Print "Action D"
               Case &H04 : Print "Action E"
               Case Else : Print "Action F"
         End Select
         Exit Sub
   End If
   'echo on PORT 7
   If T_udp_destport = &H0700 Then
            'Build The Ip Header
            Call Setipaddrs
            'swap the UDP source and destinations port
            Swap T_udp_srcport0 , T_udp_destport0
            Swap T_udp_srcport1 , T_udp_destport1
            Call Udp_checksum
            Call Echopacket
   End If
End Sub


' Routine to calculate a IP-header checksum
'
Sub Ip_header_checksum
  Local Ip_checksum16 As Word
  Local Ip_header_length As Byte
  T_ip_hdr_cksum = &H00                                     'Calc starts with chksum=0
  'Calculate IP header length
  Ip_header_length = T_ip_vers_len And &H0F                 'Number of 32 bit words
  Ip_header_length = 4 * Ip_header_length                   'Calc number of bytes
  Ip_checksum16 = Tcpchecksum(buffer(15) , Ip_header_length )
  'Store the checksum value in the packet buffer
  T_ip_hdr_cksum1 = High(ip_checksum16)
  T_ip_hdr_cksum0 = Low(ip_checksum16)
End Sub


' Routine to calculate a ICMP-checksum
'
Sub Icmp_checksum
  'Clear the ICMP checksum before starting calculation
  T_icmp_cksum = &H00
  'Calculate the ICMP checksum
  I_header_length = T_ip_pktlen1 - 20
  I_checksum16 = Tcpchecksum(buffer(35) , I_header_length ) 'built-in way
  T_icmp_cksum1 = High(i_checksum16)
  T_icmp_cksum0 = Low(i_checksum16)
End Sub


' Routine to echo packet
'
Sub Echopacket
   'packetlengte
   Hulp2 = T_udp_len0 * 256
   Hulp2 = Hulp2 + T_udp_len1
   Hulp2 = Hulp2 + 34
   Call Enc28j60packetsend(hulp2)
End Sub


' Routine to handle the source/destination address
'
Sub Setipaddrs
   T_ip_destaddr = T_ip_srcaddr
   'make ethernet module IP address source address
   T_ip_srcaddr = My_ip
   Call Src2dest
   'Set source MAC in ethernet frame, pos 7
   Call Src2mymac
   Call Ip_header_checksum
End Sub


' Routine to get the NetWork Time from a time-server
'
Sub Ntp_get
   'MAC-header
   'Destination hardware address                               ' You have to put your router-mac-address here
   T_enetpacketdest0 = &H00                                 ' 00-0c-41-ae-7a-dc MAC-address of my router
   T_enetpacketdest1 = &H0C
   T_enetpacketdest2 = &H41
   T_enetpacketdest3 = &HAE
   T_enetpacketdest4 = &H7A
   T_enetpacketdest5 = &HDC
   ' source (own source)
   Call Src2mymac
   T_enetpackettype = &H0008                                ' = &h0800
   ' fill IP-header
   T_ip_vers_len = &H45
   T_tos = &H00
   T_ip_pktlen0 = &H00
   T_ip_pktlen1 = &H30
   T_id0 = &H4A
   T_id1 = &HA5
   T_flags = &H00
   T_offset = &H00
   T_ttl = &H80
   'protocol (ICMP=1, TCP=6, UDP=11)
   T_ip_proto = &H11
   'IP address of source
   T_ip_srcaddr0 = Myip(1)
   T_ip_srcaddr1 = Myip(2)
   T_ip_srcaddr2 = Myip(3)
   T_ip_srcaddr3 = Myip(4)
   'IP address of destination                                   'you have to put the IP-number of
   T_ip_destaddr0 = 193                                     ' the NTP-server here
   T_ip_destaddr1 = 67
   T_ip_destaddr2 = 79
   T_ip_destaddr3 = 202
   'UDP-header
   T_udp_srcport0 = &H13
   T_udp_srcport1 = &H88
   T_udp_destport0 = &H00                                   ' port 0025 = 37 NTP
   T_udp_destport1 = &H25
   T_udp_len0 = &H00
   T_udp_len1 = &H1C
   T_udp_data = Asc( "X")
   T_udp_data1 = &H0A                                       ' lf
   T_udp_data2 = &H0D                                       ' cr
   Call Ip_header_checksum
   Call Udp_checksum
   Call Echopacket
End Sub


' Routine to convert the LONG from the NTP-server in to date and time
'
Sub Ntp
   S(1) = T_udp_data
   S(2) = T_udp_data1
   S(3) = T_udp_data2
   S(4) = T_udp_data3
   Swap S(1) , S(4) : Swap S(2) , S(3)
   L2 = L1 + 1139293696
   L2 = L2 + 3600                                           ' offset UTC + 1 hour
   Print "Date : " ; Date(l2)
   Print "Time : " ; Time(l2)
End Sub


'Tcp-checksum
'
Sub Tcp_checksum
   Local Whulp1 As Word
   Local Tempword2 As Word
   Tcp_cksum = 0
   Call Srcdestchksum
   'resultaat in I_chksum32
   Tempwordh = T_ip_pktlen0
   Tempwordl = T_ip_pktlen1
   I_chksum32 = I_chksum32 + Tempword
   Tempword2 = T_ip_vers_len And &H0F
   Tempword2 = Tempword2 * 4
   I_chksum32 = I_chksum32 - Tempword2
   Whulp1 = Tempword - 20
   Val2 = Highw(i_chksum32)
   Val1 = I_chksum32
   I_checksum16 = Tcpchecksum(buffer(&H23) , Whulp1 , Val2 , Val1)
   Tcp_cksuml = High(i_checksum16)
   Tcp_cksumh = Low(i_checksum16)
End Sub


' Routine to calculate the IP-checkum
'
Sub Udp_checksum
   T_udp_chksum = &H00
   Call Srcdestchksum
   'resultaat in I_chksum32
   'packet length
   I_value16h = T_udp_len0
   I_value16l = T_udp_len1
   I_chksum32 = I_chksum32 + I_value16
   Result16h = T_udp_len0
   Result16l = T_udp_len1

   Val2 = Highw(i_chksum32)
   Val1 = I_chksum32

   I_checksum16 = Tcpchecksum(buffer(&H23) , Result16 , Val1 , Val2)

   T_udp_chksum1 = High(i_checksum16)
   T_udp_chksum0 = Low(i_checksum16)
End Sub

Sub Srcdestchksum
   'checksum TCP header
   I_chksum32 = 0
   I_value16h = T_ip_srcaddr0
   I_value16l = T_ip_srcaddr1
   I_chksum32 = I_chksum32 + I_value16
   I_value16h = T_ip_srcaddr2
   I_value16l = T_ip_srcaddr3
   I_chksum32 = I_chksum32 + I_value16
   I_value16h = T_ip_destaddr0
   I_value16l = T_ip_destaddr1
   I_chksum32 = I_chksum32 + I_value16
   I_value16h = T_ip_destaddr2
   I_value16l = T_ip_destaddr3
   I_chksum32 = I_chksum32 + I_value16
   'proto
   I_chksum32 = I_chksum32 + T_ip_proto
End Sub


'HTTP
'
Sub Http
   Local Msg_temp2 As String * 10
   Local Tempstring1 As String * 1
   Local Ackpsh As Byte
   Local Pkthulp As Word
   Local Tempword1 As Word
   Local Tempword3 As Word
   Work = Tcp_flags
   Tcp_fin = Work.0
   Tcp_syn = Work.1
   Tcp_rst = Work.2
   Tcp_psh = Work.3
   Tcp_ack = Work.4
   Tcp_urg = Work.5

   ' This code segment processes the incoming SYN from the client
   ' and sends back the initial sequence number (ISN) and acknowledges
   ' the incoming SYN packet
   If Tcp_syn = 1 Then
         'Move IP source address to destination address
         T_ip_destaddr = T_ip_srcaddr
         'Make ethernet module IP address source address
         T_ip_srcaddr = My_ip
         Swap Tcp_srcportl , Tcp_destportl
         Swap Tcp_srcporth , Tcp_destporth
         Tcpdatalen_in = 1
         Client_seqnum0 = Tcp_seqnum0
         Client_seqnum1 = Tcp_seqnum1
         Client_seqnum2 = Tcp_seqnum2
         Client_seqnum3 = Tcp_seqnum3
         Client_seqnum = Client_seqnum + Tcpdatalen_in
         Tcp_acknum0 = Client_seqnum0
         Tcp_acknum1 = Client_seqnum1
         Tcp_acknum2 = Client_seqnum2
         Tcp_acknum3 = Client_seqnum3
         Tcp_seqnum0 = &HFF                                 'Initial sequencenumber
         Tcp_seqnum1 = &HFF                                 '
         Tcp_seqnum2 = &H10                                 '
         Tcp_seqnum3 = &H11                                 '
         Call Src2dest
         Set Flags.synflag
         Tcp_flags = 0
         Set Tcp_flags.1
         Set Tcp_flags.4
         T_ip_pktlen0 = &H00
         T_ip_pktlen1 = 48
         Call Ip_header_checksum
         Call Tcp_checksum
         Call Enc28j60packetsend(62)
   End If


   ' If an ACK and PSH is received and the destination port address is valid
   If Tcp_ack = 1 Then
        If Tcp_psh = 1 Then
           'set flags
           Tcp_flags = 0
           Set Tcp_flags.4                                  'ack
           'Move IP source address to destination address
           T_ip_destaddr = T_ip_srcaddr
           'Make ethernet module IP address source address
           T_ip_srcaddr = My_ip
           Swap Tcp_srcportl , Tcp_destportl
           Swap Tcp_srcporth , Tcp_destporth
           'swap mac
           Call Src2dest
           Call Inc2seq
           T_ip_pktlen = T_ip_pktlen0 * 256
           T_ip_pktlen = T_ip_pktlen + T_ip_pktlen1
           Incoming_ack = Incoming_ack + T_ip_pktlen
           Call Seq2ack
           Call Ack2inc
           Buffer(17) = 0
           Buffer(18) = 40
           '5 x 4 = 20 bytes
           Buffer(47) = &H50
           'padding
           Buffer(55) = 0
           Buffer(56) = 0
           Buffer(57) = 0
           Buffer(58) = 0
           Buffer(59) = 0
           Buffer(60) = 0
           Call Ip_header_checksum
           Call Tcp_checksum
           Call Enc28j60packetsend(60)
           Ackpsh = 1
        End If
    End If

    If Tcp_ack = 1 Then
       If Buffer(17) = 0 Then
          If Buffer(18) = 40 Then
             If Ackpsh = 1 Then
                 'ACK after a ACK-PSH
                 'set flags
                 Tcp_flags = 0
                 Set Tcp_flags.4                            'ack
                 Set Tcp_flags.3                            'psh
                 Set Tcp_flags.0                            'fin
                 'Move IP source address to destination address
                 T_ip_destaddr = T_ip_srcaddr
                 'Make ethernet module IP address source address
                 T_ip_srcaddr = My_ip
                 Swap Tcp_srcportl , Tcp_destportl
                 Swap Tcp_srcporth , Tcp_destporth
                 'swap mac
                 Call Src2dest
                 Call Inc2seq
                 Call Seq2ack
                 Call Ack2inc
                 Tempword3 = &H37
                 Restore Htmlcode
                 Do
                     Read Msg_temp
                     Msg_temp2 = Right(msg_temp , 8)
                     If Msg_temp2 = "endblock" Then
                        Exit Do
                     End If
                     If Msg_temp2 = "sizeused" Then
                        Tempword1 = Tempword3 + 24
                        Msg_temp = "<br>Used: " + Str(tempword1) + " bytes"
                     End If
                     If Msg_temp2 = "date    " Then
                        Msg_temp = Date(l2)
                     End If
                     If Msg_temp2 = "time    " Then
                        Msg_temp = Time(l2)
                     End If
                     If Msg_temp2 = "copyleft" Then
                        Msg_temp = "<br>www.benshobbycorner.nl/bzijlstra<br>"
                     endif
                     For Y = 1 To Len(msg_temp)
                         Tempstring1 = Mid(msg_temp , Y , 1)
                         Buffer(tempword3) = Asc(tempstring1)
                     Incr Tempword3
                     Next Y
                Loop
                Buffer(tempword3) = &H0D
                Incr Tempword3
                Buffer(tempword3) = &H0A
                Tempword3 = Tempword3 - 14
                Pkthulp = Tempword3 / 256
                T_ip_pktlen0 = Pkthulp
                Pkthulp = T_ip_pktlen0 * 256
                T_ip_pktlen1 = Tempword3 - Pkthulp
                Tempword3 = Tempword3 + 14
                Call Ip_header_checksum
                Call Tcp_checksum
                Call Enc28j60packetsend(tempword3)
              End If
           End If
        End If
     End If
End Sub


' TCP
'
Sub Tcp
   If Tcp_destporth = 0 Then
       If Tcp_destportl = 80 Then
          Call Http
       End If
   End If
End Sub


Sub Inc2seq
    Incoming_ack0 = Tcp_seqnum0
    Incoming_ack1 = Tcp_seqnum1
    Incoming_ack2 = Tcp_seqnum2
    Incoming_ack3 = Tcp_seqnum3
End Sub


Sub Seq2ack
    Tcp_seqnum0 = Tcp_acknum0
    Tcp_seqnum1 = Tcp_acknum1
    Tcp_seqnum2 = Tcp_acknum2
    Tcp_seqnum3 = Tcp_acknum3
End Sub


Sub Ack2inc
    Tcp_acknum0 = Incoming_ack0
    Tcp_acknum1 = Incoming_ack1
    Tcp_acknum2 = Incoming_ack2
    Tcp_acknum3 = Incoming_ack3
End Sub


Sub Src2mymac
   'Make ethernet module mac address the source address
   T_enetpacketsrc0 = Mymac(1)
   T_enetpacketsrc1 = Mymac(2)
   T_enetpacketsrc2 = Mymac(3)
   T_enetpacketsrc3 = Mymac(4)
   T_enetpacketsrc4 = Mymac(5)
   T_enetpacketsrc5 = Mymac(6)
End Sub


Sub Src2dest
   'move hardware source address to destination address
   T_enetpacketdest0 = T_enetpacketsrc0
   T_enetpacketdest1 = T_enetpacketsrc1
   T_enetpacketdest2 = T_enetpacketsrc2
   T_enetpacketdest3 = T_enetpacketsrc3
   T_enetpacketdest4 = T_enetpacketsrc4
   T_enetpacketdest5 = T_enetpacketsrc5
   Call Src2mymac
End Sub


' htmlcode
'
Htmlcode:
Data "HTTP/1.0 200" , &H0D , &H0A , &H0D , &H0A
Data "<html><head><title>Tux</title></head><body>"
Data "<img src=" , &H22 , "https://benshobbycorner.nl/bzijlstra/bens.gif" , &H22 , ">"
Data "<br><br><b>Hello Guido Socher - www.tuxgraphics.org"
Data "<br><br>About 11.500 bytes used to get<br>ARP, PING, "
Data "UDP (NTP) and TCP (HTTP) working.<br><br>"
Data "<img src=" , &H22 , "https://benshobbycorner.nl/hobbycorner/"
Data "images/tux_enc28j60.jpg" , &H22 , "><br><br>"
Data "date    "
Data "        "
Data "time    "
Data "copyleft"
Data "sizeused"
Data "endblock"