Downlink in AU915 error unsupported frequency

Channel Plan management
1

Hi all. I am working with a customized LoRa Gateway based on the SX1302. I made the integration with chirpstack and can see the uplink packages join request. Unfortunately I can not confirm the download packages. The next error appears in the package forwarder log. The frequency 0 that appears is for some parameter I missed in the global_conf.json?. I am using the legal packet forwarder and just modified the server address and the gateway eui.

*** Packet Forwarder ***
Version: 1.0.3
*** SX1302 HAL library version info ***
Version: 1.0.3;
INFO: Little endian host
INFO: found configuration file global_conf.json, parsing it
INFO: global_conf.json does contain a JSON object named SX130x_conf, parsing SX1302 parameters
INFO: spidev_path /dev/spidev0.0, lorawan_public 1, clksrc 0, full_duplex 0
INFO: antenna_gain 0 dBi
INFO: Configuring precision timestamp: max_ts_metrics:255, nb_symbols:1
INFO: Configuring Tx Gain LUT for rf_chain 0 with 16 indexes for sx1250
INFO: radio 0 enabled (type SX1250), center frequency 915600000, RSSI offset -215.399994, tx enabled 1
INFO: radio 1 enabled (type SX1250), center frequency 916400000, RSSI offset -215.399994, tx enabled 0
INFO: Lora multi-SF channel 0> radio 0, IF -400000 Hz, 125 kHz bw, SF 5 to 12
INFO: Lora multi-SF channel 1> radio 0, IF -200000 Hz, 125 kHz bw, SF 5 to 12
INFO: Lora multi-SF channel 2> radio 0, IF 0 Hz, 125 kHz bw, SF 5 to 12
INFO: Lora multi-SF channel 3> radio 0, IF 200000 Hz, 125 kHz bw, SF 5 to 12
INFO: Lora multi-SF channel 4> radio 1, IF -300000 Hz, 125 kHz bw, SF 5 to 12
INFO: Lora multi-SF channel 5> radio 1, IF -100000 Hz, 125 kHz bw, SF 5 to 12
INFO: Lora multi-SF channel 6> radio 1, IF 100000 Hz, 125 kHz bw, SF 5 to 12
INFO: Lora multi-SF channel 7> radio 1, IF 300000 Hz, 125 kHz bw, SF 5 to 12
INFO: Lora std channel> radio 0, IF 300000 Hz, 500000 Hz bw, SF 8, Explicit header
INFO: FSK channel 8 disabled
INFO: global_conf.json does contain a JSON object named gateway_conf, parsing gateway parameters
INFO: gateway MAC address is configured to 0016C001FF184912
INFO: server hostname or IP address is configured to “201.62.44.66”
INFO: upstream port is configured to “1700”
INFO: downstream port is configured to “1700”
INFO: downstream keep-alive interval is configured to 12 seconds
INFO: statistics display interval is configured to 20 seconds
INFO: upstream PUSH_DATA time-out is configured to 100 ms
INFO: packets received with a valid CRC will be forwarded
INFO: packets received with a CRC error will NOT be forwarded
INFO: packets received with no CRC will NOT be forwarded
INFO: Reference latitude is configured to -20.331750 deg
INFO: Reference longitude is configured to -40.359970 deg
INFO: Reference altitude is configured to 20 meters
INFO: Beaconing period is configured to 0 seconds
INFO: Beaconing signal will be emitted at 923300000 Hz
INFO: Beaconing channel number is set to 8
INFO: Beaconing channel frequency step is set to 600000Hz
INFO: Beaconing datarate is set to SF12
INFO: Beaconing modulation bandwidth is set to 500000Hz
INFO: Beaconing TX power is set to 27dBm
INFO: global_conf.json does contain a JSON object named debug_conf, parsing debug parameters
INFO: got 2 debug reference payload
INFO: reference payload ID 0 is 0xCAFE1234
INFO: reference payload ID 1 is 0xCAFE2345
INFO: setting debug log file name to loragw_hal.log
CoreCell reset through GPIO25…
CoreCell power enable through GPIO17…
ERROR: Failed to set SX1250_1 in STANDBY_RC mode
INFO: [main] concentrator started, packet can now be received
INFO: concentrator EUI: 0x0018v001ff165235
INFO: [down] PULL_ACK received in 7 ms
INFO: [down] PULL_ACK received in 8 ms
JSON up: {“stat”:{“time”:“2021-03-03 19:02:53 GMT”,“rxnb”:1,“rxok”:1,“rxfw”:1,“ackr”:100.0,“dwnb”:0,“txnb”:0}}
INFO: [up] PUSH_ACK received in 11 ms
INFO: [down] PULL_ACK received in 23 ms
INFO: [down] PULL_RESP received - token[122:151] :slight_smile:
JSON down: {“txpk”:{“imme”:true,“rfch”:0,“powe”:20,“ant”:0,“brd”:0,“freq”:0,“modu”:“LORA”,“datr”:“SF10BW125”,“codr”:“4/5”,“ipol”:true,“size”:16,“data”:“YEIgBEKQJQBkCmUiRNvdNA==”}}
INFO: [down] a packet will be sent in “immediate” mode
ERROR: Packet REJECTED, unsupported frequency - 0 (min:915000000,max:928000000)
INFO: [down] PULL_ACK received in 16 ms
`

2

what does your chirpstack-network-server.toml file look like?

also have you added the frequency plan in gateway profile?

Screen Shot 2021-03-04 at 6.14.28 pm
Screen Shot 2021-03-04 at 6.14.28 pm2256×878 62.3 KB

3

Thank you Sr. I discovered that one of my SX1250 is not working and thats the reason why it appears 0 Hz on the error message. My Chirpstack gateway Profile is the same as you posted. I hope I can replace the IC the next days and I will write here if the problem has been solved.

4

I have the same problem. I don’t know why.

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5

That might also be an issue, but it is not why there is a txpk specifying 0 frequency and being rejected before it gets anywhere near the hardware. Why the server or gateway bridge is creating or passing on a request with 0 frequency is the key question.

The transmit command also specifies transmission in immediate mode, which would not normally be useful in LoRaWAN when precise timing is required. Thus it must be either a class C downlink, or more likely non-LoRaWAN traffic, perhaps the optional gateway-to-gateway coverage testing “pings”.

Anyway, since that error packet is not typical LoRaWAN traffic its probably more of a “quirk” than an actual issue to normal functionality.

6

This typically indicates a reset GPIO or enable or SPI communication problem, or perhaps a configuration problem where the packet forwarder is wrong about which of the radio chips is going to provide the clock (a board can be designed either way)

While it could be a hardware failure of a given unit, most of the people seeing this are not going to have a hardware failure, but rather a connection / configuration problem.