DOWNLINK_PAYLOAD_SIZE:payload exceeds max payload size

ChirpStack Application Server
1

Hi
In the previous test, I tried to send one byte of data on the application server, and the results were all successful, but today the following problems suddenly appeared:
The code in the codec interface of device-profile:

function Encode(fPort, obj, variables) {

if(fPort==123){
var data = new Array();
data[0] = (obj.command >> 8) & 0x00FF;
data[1] = (obj.command ) & 0x00FF;
return data;
}
}
and the command in the application-detaisl interface:
image

The error occurs in application-device data interface:
image
Please help me, I don’t know why about it
Thanks!

2

Please refer to the LoRaWAN Regional Parameters document. It explains per region the max. payload size per data-rate.

1 Like
3

I got it ! Thank you

1 Like
4

Hi, I want to know how to solve the problem

5

Send a smaller payload in accordance with your region. See the referenced Regional Parameters doc.

6

Thanks，Now, I don’t know which i need to change, device setting? gateway setting? Chirpstack Region?

7

I am trying to understand this issue as well. For DR_3 in US915, I expect a payload size of 242 bytes each way, but chirpstack is limiting the downlink to 53 bytes. I can uplink 242, and my lorawan stack tells me the max payload is 242, but chirpstack blocks my downlink data for any size over 53. Is there any other setting that I am not seeing to control this?