This is a very basic LoRaWAN library.
Requirements: util.js
Platform.loadLibrary('/util.js');
Supported features:
- Activation Method: ABP
- send confirmed / un-confirmed message
- receive confirmed / un-confirmed message
- encode/decode ACK message
- decoding MAC commands (FOpts)
- send FOpts
Unsupported:
- Activation Method: OTAA
- LoraWanPacket
- LoraWanPacket.ackPacket
- LoraWanPacket.confirmedDown
- LoraWanPacket.confirmedUp
- LoraWanPacket.foptsDecode
- LoraWanPacket.makePacketFromPayLoad
- LoraWanPacket.parseDownPacket
- LoraWanPacket.unConfirmedDown
- LoraWanPacket.unConfirmedUp
- loraWanBeaconDecode
- loraWanBeaconGetNextChannel
- loraWanBeaconListen
- loraWanChannel915
- loraWanUpDownChannel915
Create a LoraWanPacket instance using device address, network key, and application key. All packet operations will use the address and keys to encode and decode packets.
Configure the frame counter length by setting member variable fcntLen to 2 for 16bit and 4 fore 32bit. The default is 16bit. The length is not used by the library, the user has to manage the fcnt.
The instance will contain the following members:
{
devAddr: plainBuffer,
nwkKey: plainBuffer,
appKey: plainBuffer,
fcntLen: int,
makePacketFromPayLoad: function,
unConfirmedUp: function,
confirmedUp: function,
ackPacket: function,
parseDownPacket: function,
}
-
devAddr
type: plain buffer
device address
-
nwkKey
type: plain buffer
network key
-
appKey
type: plain buffer
application key
Returns: LoraWanPacket object
addr = hexToBin('AABBCCDD');
appkey = hexToBin('0011223344556677889900aabbccddee');
nwkkey = hexToBin('ffeeddccbbaa00998877665544332211');
var lwp = LoraWanPacket(addr, nwkkey, appkey);
Create a UpACK packet.
-
fport
type: uint
fport
-
fcnt
type: uint
frame counter
Returns: loraWan packet as a plain buffer
pkt = lwp.ackPacket(1, 1);
Create a ConfirmedDown packet.
-
payload
type: plain buffer
payload
-
fport
type: uint
fport
-
fcnt
type: uint
frame counter
-
fopts
type: plain buffer
fopts
Returns: loraWan packet as a plain buffer
var enc = new TextEncoder();
var payload = enc.encode('hi');
var vport = 1;
var fcnt = 1;
pkt = lwp.confirmedDown(payload, fport, fcnt, []);
Create a ConfirmedUp packet.
-
payload
type: plain buffer
payload
-
fport
type: uint
fport
-
fcnt
type: uint
frame counter
-
fopts
type: plain buffer
fopts
Returns: loraWan packet as a plain buffer
var enc = new TextEncoder();
var payload = enc.encode('hi');
var vport = 1;
var fcnt = 1;
pkt = lwp.confirmedUp(payload, fport, fcnt, []);
parse FOpts to get MAC commands (not all commands are fully decoded)
-
data
type: plain buffer
fopts
Returns: array of MAC commands
var mac = lwp.foptsDecode(pkt.fopts);
// print MAC command name
print(mac[0].cmd + '
');
Create a LoraWan packet.
-
payload
type: plain buffer
payload
-
pkttype
type: uint8
packet type
-
fport
type: uint
fport
-
fcrtl
type: plain buffer
fcrtl
-
fcnt
type: uint16
frame counter
-
fopts
type: plain buffer
fopts
-
dir
type: int
direction 0 = up, 1 = down
Returns: loraWan packet as a plain buffer
var enc = new TextEncoder();
var payload = enc.encode('hi');
var vport = 1;
var fcnt = 1;
// make un-confirmed Up
pkt = lwp.makePacketFromPayLoad(payload, 0x40, fport, 0, fcnt, [], 0);
Decode a received LoraWan down packet.
The decoded object packet contains the following elements:
{
error: boolean,
devAddr: plainBuffer,
confirmed: boolean,
payload: plainBuffer,
fport: int,
fcnt: int,
fopts: plainBuffer,
ack: boolean,
fpending: boolean,
adr: boolean,
adrackreq: boolean,
micVerified: boolean,
}
-
packet
type: plain buffer
packet
Returns: decoded packet object
decodedPkt = lwp.parseDownPacket(pkt)
if (!decodedPkt.micVerified) {
print('packet integrity check failed\n');
}
Create a UnConfirmedDown packet.
-
payload
type: plain buffer
payload
-
fport
type: uint
fport
-
fcnt
type: uint
frame counter
-
fopts
type: plain buffer
fopts
Returns: loraWan packet as a plain buffer
var enc = new TextEncoder();
var payload = enc.encode('hi');
var vport = 1;
var fcnt = 1;
pkt = lwp.unConfirmedDown(payload, fport, fcnt, []);
Create a UnConfirmedUp packet.
-
payload
type: plain buffer
payload
-
fport
type: uint
fport
-
fcnt
type: uint
frame counter
-
fopts
type: plain buffer
fopts
Returns: loraWan packet as a plain buffer
var enc = new TextEncoder();
var payload = enc.encode('hi');
var vport = 1;
var fcnt = 1;
pkt = lwp.unConfirmedUp(payload, fport, fcnt, []);
Decode a LoRaWAN Class B beacon.
The beacon time uses GPS time and is 17 seconds ahead of UTC. See: https://www.usno.navy.mil/USNO/time/master-clock/leap-seconds
The beacon object contains the following members:
{
error: boolean,
msg: string, // if error == true
region: int,
time: uint, // UTC
time_stamp: uint, // time stamp from beacon
time_crc: boolean,
info: uint8,
info_crc: boolean,
lat: int,
lon: int,
}
-
pkt
type: plain buffer
packet buffer
-
region
type: int
LoRaWAN region: 0 = us-915
Returns: Beacon object
var beacon = loraWanBeaconDecode(pkt, 0)
print(beacon.time);
Get the channel number for the next beacon and seconds until the beacon arrives on the channel. This relies on the device having a accurate system time.
The next channel object contains the following members:
{
channel: int, // next channel a beacon will arrive
nextBeaconSeconds: int, // number of seconds before beacon arrives
}
Returns: next channel object
var nextBeaconChannel = loraWanBeaconGetNextChannel();
print(nextBeaconChannel.channel);
Configure the LoRa modem for receiving class B beacons on a specific channel.
-
channel
type: int
channel 0-7
-
region
type: int
LoRaWAN region: 0 = us-915
Returns: boolean
loraWanBeaconListen(0, 0);
Get the US-915 frequency for a given channel and direction
-
channel
type: int
0 - 71
-
direction
type: int
0 = up, 1 = down
Returns: frequency
var freq = loraWanChannel915(1, 0);
Get the up, down, and 2nd down frequency for a given channel in US-915. The channel object contains the following members:
{
channel: uint,
sf: uint,
bw: uint,
upFreq: double,
downFreq: double,
down2Freq: double,
}
-
channel
type: int
0 - 71
Returns: channel object for given channel
var loraRadioSettings = loraWanUpDownChannel915(1);