LED Status meaning on the SIM800L EVB V2.2

I am wondering if anyone has a link to the PDF for the SIM800L EVB V2.2. I have found the PDF for the version 1.0. What I am really after is the meaning of the indicator LEDs. I was able to connect once to the Hologram Cloud but no more. I am getting a time out on AT+IPR=19200 and sometimes on which seems really odd. If I could understand what the LEDs are trying to tell me, maybe I can figure out where things are going wrong.

The RING LED is lighting up for about 10 seconds. In which time the NET LED is blinking once per second. They both go off four about a two seconds and then the whole sequence repeats.

Just to verify, you tried this with @benstr’s latest version of the code?

Yes Chris. I picked up the latest version form @benstr’s github repo. From the MODEM side, I am not sure if it is indicating that there is a network available or no network found. But the nature of the errors on the scrip side, tell me it might not be communicating correctly with the MODEM. I is getting past the initial AT command but not much further.

I was able to send a message with this SIM through the Nova using the Raspberry Pi 3 and the CLI. One of my thoughts was just to leave the Trinket and SIM800L EVA and concentrate on the Raspberry Pi/Nova setup. … but once a problem has me, it is hard to let it go.

I know how that goes. Let me set up my device here and get back to you. Even if we can’t find the SIM800 manual, we can share what we’re doing with one another.

I took the Trinket out of the equation and connected the SIM800L EVB to a USB UART adaptor and attempted to talk directly to the MODEM. It was somewhat successful to the point of sending the actual message. This could be just a formatting issue i.e. with the CR/LF Vs message length.

Again the status lights on the SIM800L EVB changed their pattern. So a description on what it is trying to tell me would be good. From the response of the MODEM, it seems it could at least make a connection.

The dialogue went along these lines (some IP address information I have replaced with “x”.

AT
OK

AT+IPR?
+IPR?

+IPR: 0
OK

AT+CPIN?
+CPIN?

+CPIN: READY
OK

AT+CMGF=1
+CMGF=1

OK

AT+CIPSHUT
+CIPSHUT

SHUT OK

AT+CSQ
+CSQ

+CSQ: 14,0
OK

AT+CGATT?
+CGATT?

+CGATT: 1
OK

AT+CIPMUX=1
+CIPMUX=1

OK

AT+CSTT=“hologram”
+CSTT=“hologram”

OK

AT+CIICR
+CIICR

OK

AT+CIFSR

+CIFSR

xx.xxx.xxx.xx

AT+CIPSERVER=1,xxxx
+CIPSERVER=1,xxxx

OK
SERVER OK

AT+CIPSTART=1,“TCP”,“xx.xxx.xxx.xxx”,xxxx
+CIPSTART=1,“TCP”,“xx.xxx.xxx.xxx”,xxxx

OK
1, CONNECT OK

+CIPSEND=1,5AT+CIPSEND=1,5

MYMSG

MYMSG
1, SEND FAIL
1, CLOSED
+CIPCLOSE=1AT+CIPCLOSE=1

ERROR
OK

AT
OK

Call Ready

SMS Ready

I still have not worked out the meaning of the indicator LEDs but I will guess that the initial state must mean that it can find a signal and is waiting to connect. I can’t figure out why Trinket running circuit Python is not able to complete the initialisation sequence, where as with a terminal program, I can. I eventually worked it out to have a successful send using HTerm and manually entering the commands as above. The difference from above is that I did not have the message string correct for the MODEM to accept.

I consider this thread closed since I was only wanting to understand the status LEDs to know if I am getting 2G coverage. The answer is a “sort of yes”. Although I get the return message from the MODEM as a successful send, I have not seen any messages on the Console yet - though the Dashboard Usage Report does report three attempted connections from the other day. Today’s attempts and messages have not shown up yet.

Steve -

Interesting stuff! The cloud response in your image is [3,0] indicating the Auth key was invalid. You can read more in our documentation. https://hologram.io/docs/reference/cloud/embedded/

Cheers

You are right. Interesting stuff. The message and key, as far as I can see look OK. I will take this back to the Nova and work with that, now that you video session are now complete😊

We aim to be streaming machines around here! So if you have suggested topics for future streams, we’re all ears!

Bonus picture of “videozilla” our streaming setup:

If the module VCC is 5v conectit to 6v and a 2.5A and will work.

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Thanks @Andrei_Savin