th-d72-ax25 | An AX25 TNC Package for the Kenwood TH-D72A Packet Radio | Navigation library

ax25.kissTNC should work with any KISS TNC, and has been tested with several different models. Yes, ax25.kissTNC has been tested and found to work with soundmodem, which emulates a KISS TNC. The serialPort and baudRate argument properties are required. The rest are optional, and can be set after the fact. In the first example, the argument's frame property would be an array of unsigned 8-bit ints, such as provided by the ax25.kissTNC's frame event. The second example shows how you can assign values to all of the ax25.Packet object's properties upon instantiation. If no argument is provided, these properties will be set to their default values, and you should set them as needed before calling ax25.Packet.assemble(). If you're receiving AX.25 frames from something other than a KISS interface attached to a serial port, you can still use ax25.Packet for packet assembly/disassembly, and you can also use ax25.Session to maintain stateful connections. ax25.Packet.disassemble(frame) expects frame to be a plain array of unsigned 8-bit integers representing an AX.25 frame less the start/stop flags and Frame-Check Sequence (FCS.) Either your interface or some middleware must remove the flags and verify the FCS, then format the data as described before passing it off to this method. ax25.Packet.assemble() returns an array of unsigned 8-bit integers representing an AX.25 frame without start/stop flags or an FCS. Either your interface or some middleware must calculate and append the FCS to the frame, then prepend and append flags and convert the array as needed.
ax25.kissTNC Provides an API for communicating with a KISS TNC on a serial port Events Properties Methods
ax25.Packet Provides an API for crafting outbound AX.25 packets Provides an API for disassembling and inspecting inbound AX.25 packets Properties Methods
ax25.Session Provides an API for stateful connections with other packet radio stations Events Properties Methods
Notes Notes on using ax25.Packet and ax25.Session without ax25.kissTNC
opened The connection to the TNC has been opened successfully.
closed The connection to the TNC has been closed.
error An error has occurred (error details will be supplied as an argument to your callback function.)
frame A KISS frame has been received from the TNC (the enclosed AX.25 frame, less start/stop flags and FCS, will be supplied as an argument to your callback function.)
sent A KISS frame was sent to the TNC (the number of bytes sent to the TNC will be supplied as an argument to your callback function. Not very useful.)
serialPort eg. "COM1", or "/dev/ttyUSB0". (String)
baudRate eg. 1200, 9600, 115200. (Number)
txDelay Transmitter keyup delay, in milliseconds. Default: 500. (Number)
persistence Persistence, float between 0 and 1. Default: 0.25. (Number)
slotTime Slot interval, in milliseconds. Default : 100. (Number)
txTail Time to keep transmitting after packet is sent, in milliseconds (deprecated.) (Number)
fullDuplex Boolean, default: false. (Boolean)
send(frame) Sends an AX.25 frame to the TNC to be sent out over the air. (frame must be an array of unsigned 8-bit integers, representing an AX.25 frame less the flags and FCS, eg. the return value of ax25.Packet.assemble().)
setHardware(value) Most people won't need to use this ... consult your TNC's documentation.
close() Close the connection to the TNC.
exitKISS() Bring the TNC out of KISS mode (if your TNC has a terminal mode.)
destinationCallsign The destination callsign, up to six alphanumerics. (String)
destinationSSID The destination SSID, one number, 0 - 15. (Number)
sourceCallsign The source callsign, up to six alphanumerics. (String)
sourceSSID The source SSID, one number. (Number)
repeaterPath An array of { callsign : , ssid : } objects. (Array of objects)
pollFinal True if this is a poll/final packet, false otherwise. (Boolean)
command True if this is a command packet, false otherwise. Inverse of response. (Boolean)
response True if this is a response packet, false otherwise. Inverse of command. (Boolean)
type Bitfield for comparison against packet types as defined in Defs.js (eg. U_FRAME, I_FRAME, S_FRAME.) (Number)
nr Sender's receive-sequence number (N(R) in the AX.25 2.2 spec.) (Number)
ns Sender's send-sequence number (N(S) in the AX.25 2.2 spec.) (Number)
pid Protocol ID field, for comparison against PIDs defined in Defs.js. (Number)
info The information field of an I or UI frame. (Array)
infoString The information field of an I or UI frame, as a string. (String)
disassemble(frame) Where frame is an array of unsigned 8-bit integers representing an AX.25 frame (eg. the value provided by the ax25.kissTNC frame event,) disassemble frame and populate the above properties with the values found therein. (Note: if ax25.Packet is instantiated with a frame argument, this will happen automatically.) (Void)
assemble() When creating an outgoing frame, make a new ax25.Packet object, populate its properties as desired, then call ax25.Packet.assemble(), which will return an array of numbers representing an AX.25 frame (which can be supplied to ax25.kissTNC.send(frame).) (Array)
log() Returns a line of text describing some of the packet's properties, suitable for logging purposes. (String)
packet An outgoing packet is ready for transmission. Your callback will be provided with an ax25.Packet object which can be sent with ax25.kissTNC.send(packet.assemble());
data Data (I or UI frame payload) has been received from the remote station. Your callback will be provided with an array of uint 8 bytes. (ax25.Utils.byteArrayToString(arr) can turn this into a string for your convenience.)
connection The connection state has changed. Your callback will be provided with a boolean value. True means that a connection has been established. False means that the connection has been closed. (Note that the connection may occasionally be re-established without a disconnection happening as part of a reset procedure.)
error Something done borked. Your callback will be provided with a helpful textual error message.
connected Whether or not a connection has been established with the remote station. (Boolean)
connection More fine-grained connection-state info than connected. (Number) 1 = Disconnected. (Not connected, not trying to connect or disconnect.) 2 = Connected. (Connected and ready.) 3 = Connecting. (Attempting to connect, waiting for acknowledgement or timeout.) 4 = Disconnecting. (Requested disconnect, waiting for acknowledgement or timeout.)
remoteCallsign The remote station's callsign, up to six alphanumerics. (String)
remoteSSID The remote station's SSID, one number, 0 - 15. (Number)
sourceCallsign The local station's (your) callsign, up to six alphanumerics. (String)
sourceSSID The local station's SSID, one number, 0 - 15. (Number)
repeaterPath An array of { callsign : , ssid : } objects. (Array of objects)
maxFrames Maximum number of unacknowledged I frames out at any given time. Default: 4. (Number) If in modulo 128 mode, the maximum value is 127; otherwise the maximum is 7.
packetLength Maximum packet payload size, in bytes, minimum of 1. Default: 256. Smaller values such as 64 are best for crappy links. The spec says 256 is the maximum, so don't expect most TNCs to support larger values. (Number)
retries How many times to poll the other station for a response before giving up. Default: 5. You may wish to raise this value if using a very busy frequency, etc. (Number)
hBaud The baud rate of over-the-air communications. Default: 1200. It's recommended that you set this if your value differs from the default, as polling intervals and other timeouts are calculated based on this figure, among others. (Number)
modulo128 (Boolean) If set prior to a connect() attempt, will attempt to send a SABME command to initiate a connection with modulo 128 sequence numbers. If read during the connected state, indicates whether the sequence numbers for this session are modulo 128. (Could be useful for tweaking the maxFrames value.) Modulo 128 implementation is in progress. Setting this value will have undesirable results for the time being.
connect() Opens a connection to another station. Remote and Local callsign and SSID properties must be set first. (Void)
disconnect() Disconnect from the remote station. (Void)
send(info) Send array of bytes (uint 8) 'info' to the remote station. (Void) (Note: 'info' is just a plain old Array(). We may switch to Uint8Array or Buffer at some point.)
sendString(str) Send string 'str' to the remote station. (Void)
receive(packet) Process and respond to the received (and disassembled) packet 'packet'. (Void)
ax25.Session if attempted SABME but failed and reconnecting with SABM, reset maxFrames to sane value Implement oustanding portions of AX.25 2.2 spec sections 4.3.2.4, 4.4.4, 6.4.4.2, 6.4.4.3, 6.4.8 re: sending and receiving SREJ add SREJ case to Session.receive() retransmit the requested frame, with a retry event scheduled track retransmitted frames and their timed events clear timed event when remote N(R) > the retransmitted frame send SREJ if: settings.modulo128 is true state.sentREJ is false a properly-sequenced packet has been received this session any out-of-sequence packet is received set state.sentSREJ an SREJ is sent (code is in place to not send REJ if this is true) if settings.modulo128 is true, push received but out-of-sequence I frames into state.receiveBuffer to be handled when previously missed frames have been received push into an array the sequence numbers of frames that have been requested for retransmission via SREJ, splice them out once they have been received, clear state.sentSREJ condition once this array is zero-length schedule timed event for retransmitting SREJ, do not push sequence number into SREJ-request tracking array additional times implement various P/F C/R minutiae and any other remaining portions of the above-mentioned parts of the specification use of SREJ probably doesn't need to hinge on modulo 128 operation; remote capability should be determined by XID parameter negotiation if/when that gets implemented. until XID is implemented, possibly watch for returned SREJ frames in U_FRMR frames from remote, sending plain REJ instead (if that's the expected response)
Implement XID frame type in Packet.js and Session.js (placeholders currently exist) In ax25.Session, various items such as maxFrames, modulo 128 operation, SREJ compatibility, etc. will need to be refactored, with decisions made based on a store of remote capabilities
YAPP file transfers in Session or additional submodule Or some other file transfer mechanism if something better came along and has seen some uptake