Meaning of downlink ack errors

axu217 · December 28, 2018, 7:02am

COLLISION_PACKET - How is this determined ahead of time? Is there a minimum time that two packets must be apart from each other?

TOO_EARLY - How early is too early?

brocaar · December 28, 2018, 9:15am

Please see:

github.com

Lora-net/packet_forwarder/blob/master/PROTOCOL.TXT#L418


	"txpk_ack": {...}
}
```


That object contain status information concerning the associated PULL_RESP packet.


 Name |  Type  | Function
:----:|:------:|------------------------------------------------------------------------------
error | string | Indication about success or type of failure that occured for downlink request.


The possible values of "error" field are:


 Value             | Definition
:-----------------:|---------------------------------------------------------------------
 NONE              | Packet has been programmed for downlink
 TOO_LATE          | Rejected because it was already too late to program this packet for downlink
 TOO_EARLY         | Rejected because downlink packet timestamp is too much in advance
 COLLISION_PACKET  | Rejected because there was already a packet programmed in requested timeframe
 COLLISION_BEACON  | Rejected because there was already a beacon planned in requested timeframe
 TX_FREQ           | Rejected because requested frequency is not supported by TX RF chain
 TX_POWER          | Rejected because requested power is not supported by gateway

myname · March 31, 2020, 5:23am

Hi… I face the TX_FREQ error after sending downlink data. Which configuration in Chirpstack reflects this setup? and how to troubleshoot this?

brocaar · March 31, 2020, 7:25am

This error comes from the gateway and indicates it can’t transmit on the requested frequency. This could be:

Because the requested frequency is invalid
The gateway is misconfigured (min / max TX frequency configuration)

myname · March 31, 2020, 2:14pm

Hi @brocaar. Thank you for the reply.

I managed to get it work after I reset and reconfigure the gateway. Thank you.

myname · April 2, 2020, 4:11am

Hi @brocaar. I faced this problem once again. I have reset the gateway and reconfigure everything in Chirpstack but still unsolved.

I’m using Gemtek gateway with AS923 frequency. I have set the RX2 frequency as per gateway configuration. Anything that I missed?