How do I get clean AT Command Output on my ESP32 38 PINS and my SIMA7670E? Using Arduino IDE at Serial Monitor

Projects General Guidance
21

I'll try this thanks!

22

usually get continuous garbage printing when baud rate is wrong or there is noise on the GPIO input

23

Wrong voltage for the Tx/Rx pins - if any - might also play a role as well as available power for the module.

24

what happens if you switch off the 5V external power supply to the modem and just power the ESP32 via USB - do you still get garbage printed?

you need the datasheet on the SIMA7670E modem!

25

Understand that you may have eliminated a possibility. That’s a positive move.

Often troubleshooting amounts to eliminating unknowns (even removing code sections) to get down to the real bug.

Garbled serial is usually a transmit-and-receive problem, like when the sketch codes for115200 and serial monitor is set for 9600. It’s a quick and easy check/fix.

PS – after reading the thread it looks like you hit another Q&E problem…. your settings may still not match! But I bet a dollar that you’ll double-check that before you run it again!

26

The ESP32 is being power via micro USB

IMG_20251028_232200_680
IMG_20251028_232200_6801920×1440 134 KB

27

After those trial and errors I have make it output what I want :folded_hands: Clean AT Commands ESP32 and A7670E

IMG_20251028_232146_993
IMG_20251028_232146_9931920×2560 465 KB

Just connected the VDD to 3.3V of ESP32
and use Pin 16,17 for rx and tx

  • with no level shifter needed
28

your code really help me a lot especially I got confused how every works but with trial and error I realize that it work at pin 16 and 17. Retry using the 18, 19 but produces garbage thank you guys!

29

My ESP32 TX and RX as far as I know produces 3.3V making it compatible to the A7670E, so I didn't use level shifter but yeah thank you also for helping me! appreciated it man!

30

shows the problem of the lack of technical documentation with this module

I looked on Amazon and Ebay - lots of these modules - nice pictures and lots of sales talk - but no technical documentation

31

Yes bro :sob:, I've been figuring this our for a week :laughing:

32

I also don't see any datasheet specified for a7670e at SimCom website :pensive_face:

33

lot of information SIMCOM A7670X product details

however, that would only cover the A7600X which it fitted to a PCB module along with other components - it is the datasheet on the finished PCB module which is required

34

I didn't know that there was A7670X I only see these when I look for it

image
image1365×660 93.6 KB

35

I am facing the same issue,can you tell me what changed did you do apart from 16,17 pins?

36

im having the same problem, can you give me the code sketch and the wiring diagram of it?