Issue: Hello, I am using a RAK811 shield with my Arduino.
According to LoRaWAN™ 1.0.2 Regional Parameters page 41, and based on the answers
here , I should be able to send my data 133 - 8 = 125 bytes at DR4 with UplinkDwellTime = 1 (8 bytes is used for FOpts and verification).
However, I am only able to at most 64 bytes in this configuration.
May I know if there is any way to send a payload of larger than 64 bytes in DR4?
Setup: PiSupply LoRa Node shield (RAK811) AS923
Server: Chirpstack
Also, if I am not able to exceed 64 bytes anyways, is there any way for me to turn UplinkDwellTime to 0 on my Arduino shield? If there’s a way, how am I supposed to do that?
Nicholas
(nicholas)
April 3, 2020, 4:05am
3
you need refer lora status,and confirm Dr = 4(at+get_config=lora:status).It could be more than 64 bytes at Dr =4.
kygoh
(kygoh)
April 5, 2020, 1:43am
4
If I am not mistaken, even though DR=4 can be more than 64 bytes the payload length is limited by the check in at_cmd.c
More specifically, line 730 of the code:
static void lora_send(int argc, char *argv[])
{
...
uint8_t *app_data = (uint8_t *)argv[3];
...
app_len = strlen(app_data);
if (app_len > 128) {
out_error(RAK_ARG_ERR);
return;
}
if (app_len%2) {
out_error(RAK_ARG_ERR);
return;
}
...
ret = rw_LoRaTxData(confirm, app_port, app_len, app_data);
...
}
The check prevents the code from proceeding to rw_LoRaTxData (line 752 in at_cmd.c) which actually goes on to check regional parameters.
Could this be the reason that even at DR=4 the payload cannot be more than 64 bytes?
Nicholas
(nicholas)
April 7, 2020, 1:46am
5
I would like to provide more information regarding this issue.
When I was trying to send 65 bytes at DR4 via AT-command, I received feedback of ERROR-1 at the serial monitor.
So… does that mean there’s no way to send anything that is larger than 64 bytes?
Nicholas
(nicholas)
April 7, 2020, 2:09am
8
Could you tell me the version number you are using?
AT command:at+version
I am using 2.0.3.0, it’s an Arduino RAK811 shield by PiSupply.
Nicholas
(nicholas)
April 7, 2020, 2:58am
10
Your version is too early. It is recommended that you upgrade the firmware to fix the problem.
May I know which firmware version will fix this? How am I supposed to update the firmware?
Thank you.
Nicholas
(nicholas)
April 7, 2020, 3:42am
12
Can you send your email to me? I will send you the operation steps.
How can I give you my email privately? Can you give me an address for me to email you instead?
Nicholas
(nicholas)
April 7, 2020, 3:57am
14