Interested to know how
How do I setup an Arduino with RFM95 Node to use always the same channel (for use with a single channel gateway)?
The following code doesnât work (found here: Single Channel Gateway part 2) . The channel is still switched:
for (int channel=1; channel<72; ++channel) {
LMIC_disableChannel(channel);
}
LMIC.freq = 868100000;
Second Question:
If I use the single channel gateway from @JBraam with the settings (GW_SF = âALLâ), I get ârx timeoutâ.
The node and the ESP8266 single channel gateway are in 0.5m distance of each other. With the settings (GW_SF = âSF7â) it works.
Got the first question solved:
In the lmic library I set in the lmic.h file MAX_CHANNELS = 1
Now the arduino node uses always the same channel for TX.
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Hey Roshan007, sorry for delay, I used a mix
and
http://things4u.github.io/DeveloperGuide/designing_1ch_gateway/ESP-gateway-4.html
on the GW I used STD mode, fixed to SF 7 and a specific up & down, also, used strict mode.
Also, you would be mad to do a gateway or node without first making a frequency scanner/ lora visualiser. I used GQRX and RTL-SDR with a $30 USB RTL2832U-based DVB-T dongle. I can see the packets - itâs like having supermanâs x-ray vision. 
Cheers
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Hi everybody,
Itâs my first time handling with these devices, so Iâm quite lost and I need some help. I recently ran the single packet forwader, and it seems that the server recognizes my Gateway (status connected), but in the Traffic tab it shows nothing about the data transfered. Should it appear something on the screen? Or maybe is it normal, because of the packetâs features?
Thank you so much in advance
Just to clarify, the traffic tab shows no entries? Usually it would show entries that correspond with data sent by nodes that passed through the gateway. If you setup a gateway but have no nodes then you wonât see any traffic.
That might be the reason, I havenât set up a node yet! Following that, I have another question. Iâm using an Arduino Mega 2560 and a Dragino Lora Shield as a node. Apart from the NWSKEY, APPSKEY and DEVADDR, what should I modify in the sketch?(itâs the same used by @thechapu ) Because once I upload it, it always shows these errors:
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_getsync(): timeout communicating with programmer
And I donât know why they appear
Thanks in advance
Remove the shield then program the Mega
Iâm using an Arduino Uno with a Dragino lora had (RF96) for the US, it should be 915000000. My Raspberry Pi on the other Dragino hat is pinging TTn.
I am using the LMIC libraries, and a hello world sketch pin mapped:
// Pin mapping
const lmic_pinmap lmic_pins = {
.nss = 10,
.rxtx = LMIC_UNUSED_PIN,
.rst = 9,
.dio = {2, 6, 7},
};
and LMIC config.h
#define CFG_us915 1
// This is the SX1272/SX1273 radio, which is also used on the HopeRF
// RFM92 boards.
//#define CFG_sx1272_radio 1
// This is the SX1276/SX1277/SX1278/SX1279 radio, which is also used on
// the HopeRF RFM95 boards.
#define CFG_sx1276_radio 1
when i connect the node and check the serial output i get this:
Starting
Packet queued
903900000
211338: EV_TXCOMPLETE (includes waiting for RX windows)
Packet queued
903900000
4182735: EV_TXCOMPLETE (includes waiting for RX windows)
am I not on the right frequency?
Using Dragino hat. I have followed along with several tutorials/write-ups and still unable to connect. Showing:
It looks like you are trying to register a gateway by EUI. This probably means you are using the legacy packet forwarder.
Status
not connected
Frequency Plan
United States915MHz
Router
ttn-router-us-west
Is it a must to use basic_pkt_fwd? If so, where to I put these .h, .c files? Do I add them to main.cpp? I am new to this and trying to learn. Any help will be appreciated. Thank you
Thank you. I have used this one and several others. Trying from home now and still will not connect. Any suggestions?
Hi everybody,
I built a single channel gateway with Dragino LoRa Pi hat and RPi 3 and connected it to the TTN. It seems to work fine, in serial console I can see messages like this:
SX1276 detected, starting.
Gateway ID: b8:27:eb:ff:ff:dd:f8:f7
Listening at SF7 on 868.100000 Mhz.
------------------
stat update: {"stat":{"time":"2017-06-17 10:59:28 GMT","lati":50.69827,"long":6.09635,"alti":274,"rxnb":0,"rxok":0,"rxfw":0,"ackr":0.0,"dwnb":0,"txnb":0,"pfrm":"Single Channel Gateway","mail":"hans.schneider@gmx.ch","desc":"built with RPi 3 and LoRa/GPS hat"}}
stat update: {"stat":{"time":"2017-06-17 10:59:58 GMT","lati":50.69827,"long":6.09635,"alti":274,"rxnb":0,"rxok":0,"rxfw":0,"ackr":0.0,"dwnb":0,"txnb":0,"pfrm":"Single Channel Gateway","mail":"hans.schneider@gmx.ch","desc":"built with RPi 3 and LoRa/GPS hat"}}
stat update: {"stat":{"time":"2017-06-17 11:00:28 GMT","lati":50.69827,"long":6.09635,"alti":274,"rxnb":0,"rxok":0,"rxfw":0,"ackr":0.0,"dwnb":0,"txnb":0,"pfrm":"Single Channel Gateway","mail":"hans.schneider@gmx.ch","desc":"built with RPi 3 and LoRa/GPS hat"}}
Packet RSSI: -72, RSSI: -114, SNR: 9, Length: 23
rxpk update: {"rxpk":[{"tmst":3505585321,"chan":0,"rfch":0,"freq":868.100000,"stat":1,"modu":"LORA","datr":"SF7BW125","codr":"4/5","lsnr":9,"rssi":-72,"size":23,"data":"ABNSAPB+1bNwzMgeAAujBAA1GWNudvI="}]}
After that I commissioned my LoRa KISS from E&A Utrecht by hand and tried to get it connected with the new single channel gateway. Of course I did the needed changes in the sketch like OVERRIDE = true, set my appEUI and appKey. I tried with several SF but unfortunately it doesnât work at all. I got messages like this:
--- Resetting RN module
Model: RN2483
Version: 1.0.1
Sending: mac set deveui 0004A30B001EC8CC
Sending: mac set adr off
--- Random Seed
-- hwEui read from module: 0004A30B001EC8CC
-- seed: 52364
--- I2C Accelerometer initialized
Sending: mac set rx2 3 869525000
Sending: mac set ch drrange 1 0 6
Sending: mac set ch dcycle 0 799
Sending: mac set ch dcycle 1 799
Sending: mac set ch dcycle 2 799
Sending: mac set ch dcycle 3 799
Sending: mac set ch freq 3 867100000
Sending: mac set ch drrange 3 0 5
Sending: mac set ch status 3 on
Sending: mac set ch dcycle 4 799
Sending: mac set ch freq 4 867300000
Sending: mac set ch drrange 4 0 5
Sending: mac set ch status 4 on
Sending: mac set ch dcycle 5 799
Sending: mac set ch freq 5 867500000
Sending: mac set ch drrange 5 0 5
Sending: mac set ch status 5 on
Sending: mac set ch dcycle 6 799
Sending: mac set ch freq 6 867700000
Sending: mac set ch drrange 6 0 5
Sending: mac set ch status 6 on
Sending: mac set ch dcycle 7 799
Sending: mac set ch freq 7 867900000
Sending: mac set ch drrange 7 0 5
Sending: mac set ch status 7 on
Sending: mac set pwridx 1
Sending: mac set retx 7
Sending: mac set dr 5
Sending: mac join otaa
Join not accepted: denied
Check your coverage, keys and backend status.
Sending: mac join otaa
Join not accepted: denied
Check your coverage, keys and backend status.
Sending: mac join otaa
Join not accepted: denied
Check your coverage, keys and backend status.
Sending: mac join otaa
Join not accepted: denied
Check your coverage, keys and backend status.
Sending: mac join otaa
Response is not OK: no_free_ch
Send join command failed
I even deleted the device in TTN console and created it new with new appEUI and appKey. I also did a gateway reset and started it again but the result is always the same. Gateway and LoRa Kiss are in the same room so it isnât a coverage problem. The gateway is connected.
What went wrong? Any suggestions?
Hans
âPacket RSSI: -72, RSSI: -114, SNR: 9â
I think your RSSI is to high. I was not able to see node packets if RSSI wasnât in the -40 to -50 range. Try setting your SNR to 7 in the gateway.
Can anybody tell me how to set SNR in single_chan-pkt-fwd?
I set the number of join retries to -1 because I want to retry indefinatly (RETRIES = -1).
I get the message that there is no free channel and my KISS LoRa Gadget can not join. What is blocking my single channel? I have only this device and no other is present.
Does the gateway console show up- and downlink packets for your gateway?
No, it doesnât show up- and downlink packets. What is going wrong and better: How can I fix it?
No up- and downlink packets means your gateway is not receiving data. Make sure the settings of your node match the settings of the gateway, which means the node should transmit using SF7 (dr5) on 868.1 MHz.
As you are using a RN2483 based node which is setup to use 8 channels (looking at the log you posted earlier) there is a 1 in 8 chance the randomly chosen channel will match your limited gateway. (There is a reason full gateways use 8 channels 
)
As the gadget retries the joins with a minimal (too small) delay it will hit the airtime limits within a few retries and youâll likely need a lot of retries.
I havenât looked at the code for the gadget (yet) but first thing I would try is to increase the amount of time between join attempts to 1 minute. Next make sure there is at least 3 meters between the gateway and the gadget, power on the gadget and be patient⌠(open the gateway console and check if any traffic is listed after about 1 hour)
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Thank you for the suggestion but it seems not to work.
The KISS LoRa is now trying to join for about 12 hours (RETRIES = -1) and I still canât see any data coming in. SF is 7, both KISS and single channel gateway.