Hello @ramaker

from looking at both schematics (M5Core Fire and GoPlus) I'd say:

An external power supply will power the M5Core Fire, but it won't charge the battery. (If you look at the M5Core Fire schematic you'll see that only USB can charge the battery, but not the 5 volts coming from the GoPlus).

Depends on the motors and the USB power supply. If the USB power supply is strong enough it should be able to power both, M5CoreFire and the motor.

The voltage for the motor will be lower with option 2 - probably in the area of 4.6 volts. Whereas with option 1 it will be in the area of 6 volts.

Please note: I derived all of the above information purely from looking at the schematics as I don't have the GoPlus module myself, so I could be missing something and my conclusions could be incorrect.

Thanks
Felix

@dukenukke M5Stack library contains an error in LoRaWan.cpp
the definition of first element of array:
const char *physTypeStr[10] = {"EU434", "EU868"....
should be like this:
const char *physTypeStr[10] = {"EU433", "EU868"....
Since module RHF76 doesn't understand command like
AT+DR=EU434

Hi Again,
After some months with my module in "Stand By" I restart again my project using it and I found this info! Thanks a lot I will upgrade the GRBL of it

It is safe, but the battery will charge each other.

@jmakiv I am curious about this as well. I got the module and my sim card from Deutsche Telekom should arrive tomorrow.

I followed up on this project with another that's a real calculator. It was more work than I had anticipated; that might explain why there are so few examples: https://github.com/vkichline/FullCalculator-Arduino
The README includes pictures this time.

Hello John

A couple of M5Stack modules (like GPS) already use a serial connection via GPIO16 and GPIO17. However GPIOs only provide logical voltage levels (0V / +3.3V).

Assuming your source is a standard RS232 device the voltage levels can go down to -15V and up to +15V so you probably need a level converter like this one:

https://www.amazon.com/Serial-Converter-Equipment-Upgrades-Doupont/dp/B01N42QW8X/ref=sr_1_6?crid=2OZ5U3Q7GY5OS&dchild=1&keywords=ttl+rs232+converter&qid=1597992249&sprefix=ttl+rs2%2Caps%2C276&sr=8-6

Cheers
Felix

Hello again

I think the following library should allow you to switch between WiFi or Ethernet OTA:

https://github.com/espressif/arduino-esp32/tree/master/libraries/Update

Use it with either a WiFiClient or EthernetClient client.

Cheers
Felix

@m5stack Hello!

I would like to know to which bronchi pins A and B of the RS485 extension card are connected to the BUS, please.

I can't get my M5 to communicate via RS485, however I soldered the small expansion card well.
For my program I am using an ESP32 based Arduino library for the Modbus RTU

@ardo Yes, you could connect they together.

So, after many experiments I'm sorry to report that the RS-485 Atom module has very bad Rx characteristics.

The issue of getting corrupted data was related to problems in the serial support of the arduino-esp32 project. After moving to git version I still had several problems:

missing bytes zero byte at end of rx block last byte of block was sometimes corrupted

I've then tried replacing the RS-485 Hat with another RS485-to-RS422 adapter and since then it works flawlessly. Something in the electrical design of the RS-485 hat must be messing up the Rx data.

Hi FunkyFab

interesting... Thanks for sharing. Glad you got it working again.

Cheers
Felix

Thanks so much ! This is the information I eager to have.