I also have a Adafruit Feather 32u4 LoRa Radio up and running based on the “IBM LMIC framework” library included via the Arduino IDE. It seems this originates from Matthijs Kooijman’s work for Arduino platforms.
// Pin map for Adafruit Feather 32u4 LoRa
const lmic_pinmap lmic_pins = {
.nss = 8,
.rxtx = LMIC_UNUSED_PIN,
.rst = 4,
.dio = {7, 6, LMIC_UNUSED_PIN},
};
I have connected IO1 to digital pin 6 with a wire bridge.
I modified the code to join TTN using OTAA.
But now I experience a strange behaviour:
- The node sends join requests, and every single join request arrives at TTN, as I can see the “Activation” messages in TTN console
- However, the node does not receive any response from TTN. As it does not receive responses, it just keeps trying to send join requests.
- Both join receive windows (5s and 5+1s) are missed
- Only the sixth or seventh join request is successful: The node receives the response from TTN.
- I am using a Kerlink LoRa IoT Station as gateway which is located in a room next to me
- Tries in the order of appearance: SF7@867,5 - SF7@868,1 - SF8@868,3 - SF8@868,5 - SF9@867,1 - SF9@867,3 - SF10@867,5
The gateway is located in a room next to me - why does it obviously need SF10 in order to enable the node to actually receive the response from TTN? I would possibly understand if the gateway would be located far away from the node, but it isn’t.
Is this possibly an issue of the timing of the join receive windows in the nodes? It is hard to believe that the code provided by Matthijs Kooijman really works for each and every Arduino based hardware. Is there some place in the code where these receive windows need to be adjusted?
5539776: WK --- IRQ Handler 0 // Join message #1 sent
10548152: WK --- IRQ Handler 1 // Receive timeout in join receive window 1 (5s)
11754072: WK --- IRQ Handler 1 // Receive timeout in join receive window 2 (5+1s)
21323944: WK --- IRQ Handler 0 // Join message #2 sent
26332368: WK --- IRQ Handler 1
27538304: WK --- IRQ Handler 1
42022208: WK --- IRQ Handler 0 // Join message #3 sent
47037272: WK --- IRQ Handler 1
48236584: WK --- IRQ Handler 1
66233032: WK --- IRQ Handler 0 // Join message #4 sent
71248144: WK --- IRQ Handler 1
72447408: WK --- IRQ Handler 1
77584832: WK --- IRQ Handler 0 // Join message #5 sent
82613200: WK --- IRQ Handler 1
83799200: WK --- IRQ Handler 1
113588872: WK --- IRQ Handler 0 // Join message #6 sent
118617336: WK --- IRQ Handler 1
119803320: WK --- IRQ Handler 1
161840632: WK --- IRQ Handler 0 // Join message #7 sent
EV_JOINED