I tried your script and all the leds work fine and so does the button. Its difficult to āwiggleā the backplane as its screwed down tight on standffs.
I have pin 22 (RESET) jumpered to the blue led so I know when the RESET pulse is sent but the ic880a doesnāt react to it at all.
I donāt think its a backplane or a hardware issue as exactly the same thing happens with my ātestā gateway which is just an RPi3B jumpered to an ic880a. When I re-boot, the ic880a fails to respond to the RESET signal and the gateway doesnāt start.
UPDATE
Just now the ic880a āsawā the RESET pulse and the gateway started up all by its own.
Now thatās magic!
Hah, thatās a good idea 
Yeah, not sure what the cause could be in that case. Maybe formatting the SD card and setting up the whole OS + gateway config again might help.
Done that umpteen times - no joy.
I wouldnāt mind if it was just one gateway that was misbehaving like this but both of them are doing it.
I have two batches of ic880s and so far it only did that on one (OLDER batch)ā¦ the other (belonging to a different/newer batch) is still aliveā¦ waiting for it to (knock on wood) āmisbehaveā. the one that āmisbehavedā before had # 0488 on the small square label and # 003609 on the large label ~13.2mm x 11.2mm. the NEWER batch that is still working have # 0038 on the small label and # 003892 on another, the label being ~13.2mm x 7.0mm. Iāll do some more tests (run the gateways in parallel to see if behavior is different for each one).
Iām glad (sort of) that Iām not the only one with this problem.
When I raised a ticket with IMST, I was given these instructions to take some diagnostics -
ā¢ Please clone / download the github repositry located at: GitHub - Lora-net/lora_gateway: Driver/HAL to build a gateway using a concentrator board based on Semtech SX1301 multi-channel modem and SX1257/SX1255 RF transceivers.
ā¢ Edit the file lora_gateway/libloragw/library.cfg at master Ā· Lora-net/lora_gateway Ā· GitHub and set the āDEBUG_HALā option to 1
ā¢compile everything by using the āmakeā command in the main directory
ā¢modifiy the lora_gateway/reset_lgw.sh at master Ā· Lora-net/lora_gateway Ā· GitHub script:ā¦change the reset pin to your needs
ā¦remove line 37 / make sure to keep the reset signal as output
ā¦OR: disconnect the RSET line and do a manual reset sequence
ā¢enter the lora_gateway/util_pkt_logger at master Ā· Lora-net/lora_gateway Ā· GitHub directory, start the tool and log the output
ā¢enter the lora_gateway/util_spi_stress at master Ā· Lora-net/lora_gateway Ā· GitHub directory and āplayā a little bit with this tool while logging the output.
Iāve set the DEBOG_HAL to 1 and all I get is - 31.07.17 21:53:10 (+0000) ERROR: FAIL TO CONNECT BOARD
I donāt know how to do the last 2 steps - start the tool and log the output and āplayā a little bit with this tool while logging the output. I canāt find these 2 directories in my resin build. Maybe they are not there and I need to adjust my /dev/build.sh file to get them complied - I donāt know.
The white labels on the board are Batch and Serial numbers.
Mine is 0350 and 003959 on one
and (canāt see it) and 003506 on the other.
I was asked for these when I opened a ticket.
Same error with me until I discovered that fysical pin 22 (RPi) has to be GPIO25. Problem solved
Yes - thatās how my backplane is physically wired but the ic880a still doesnāt respond to the RESET pulse.
In your log there is a pin 22 mentioned (physical pin), instead of 25 (gpio number of pin 22):
This is a part of the Resin.io log -
31.07.17 22:49:09 (+0000) [TTN Gateway]: Resetting concentrator on pin 22
31.07.17 22:49:10 (+0000) *** Multi Protocol Packet Forwarder for Lora Gateway ***
So I presumed that was the same configuration typo as I had, I changed in my configfile reset-pin 22 in reset-pin 25 and it worked like a charm
OK - I set the GW_RESET_PIN to 25 and now I get this error as pin 25 on the RPi3 is a GND pin -
16.08.17 23:52:01 (+0000) INFO: [main] Starting the concentrator
16.08.17 23:52:01 (+0000) ERROR: [main] failed to start the concentrator
16.08.17 23:52:13 (+0000) [TTN Gateway]: Resetting concentrator on pin 25
16.08.17 23:52:13 (+0000) Canāt interpret 25 as a valid pin number.
16.08.17 23:52:13 (+0000) *** Multi Protocol Packet Forwarder for Lora Gateway ***
16.08.17 23:52:13 (+0000) Version: 3.0.0
Can you find a non-LoRa way to toggle the GPIO pin up and down (from the raspberry pi) and confirm as far into the Ic880a board as you can that you see it go to a logical 0 and 1? (With a multimeter and the other lead going to a rPi ground.) Maybe its something easy like a loose solder joint somewhere. (It happens, especially with this sort of low volume stuff.)
Iād suspect easy things like voltages, physical connections, and such before suspecting higher levels like silicon being bad or software being bad. (Are you sure that power supply doesnāt have current limiting mode enabled? Have you take a multimeter to it and looked to see how much AC ripple is on it? How far down does the 5Vdc line go down when thereās load? (If at all.) )
Iām fairly certain the pin 25 is translated to the appropriate GPIO. (But adding that into the debug text output should have been done to avoid this kind of confusionā¦)
OK - I will check the voltages to see whatās going on.
Is it possible to lower the SPI speed as a config parameter? On several fora this is mentioned as a solution to look into
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SPI communication speed is fixed in the sources. To change a recompile of the code (libloragw, setting is in the concentrator specific include file, so libloragw/inc/imst_rpi.h for iC880a) will be required.
@basswildens any pointers to the forums?
This topic on GitHub has some testing on SPI speed vs error rate
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Yes it is.
I just done it - and it works!! 
You have to edit the lora_gateway/libloragw/inc/imst_rpi.h file and change the default #define SPI_SPEED 8000000 to #define SPI_SPEED 500000
I then rebuilt the code on resin.io and pushed it to both my gateways and now they start first time - even after a re-boot!
Job done!
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Also some interesting stuff on SPI clock speed on de raspi docu. Looks like clockspeed isnāt just the rounded number in our config file
And some behavior-as-expected from the developers of raspi Linux
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Hi Mr.
I have exactly the same problem as you have, I think to change the SPI speed might be solution for this problem. Since I am not understand very much about what you re discussing, would you mind show me how to change the speed in more details ?? thank you in advance.
this topic is āsolvedā
pls start a new topic and describe exactly YOUR problem 