Xiao Expanxn Base...read batt status for Meshtaxc

Products & Technology XIAO
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Hello –

Couple comments and questions…

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Running this setup on battery…well, it sure would be helpful if battery charge levels would print to screen, instead of showing “USB”. I like to see that status also displayed in the Meshtastic app node listing.

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Reviewing the schem seems only method is to maybe solder a voltage divider behind the J2 connxn, drag a wire over to the A0/D0 grove header? Is A0 the pin to use? Is that what Meshtastic would read to provide batt status?

Thanks.

Edit: nodes FA34 and BB30 are my nodes and can see…

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I was outside getting that board to lock sats and noticed the how battery status displayed…POST!

Inside I read this:
https://forum.seeedstudio.com/t/expansion-board-base-for-xiao-level-battery/284110

Lemme do some more reading. I am though interested specifically in getting batt status pushed to Meshtastic

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Grove - Rotary Angle Sensor (panel mount version), compatible with both Arduino and Raspberry Pi - Seeed Studio try this unit on D0 Grove port and see if you can use it as a voltage divider… I wanted to always try this

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Thanks for the comeback.

I been browsing the Heltec V3 schema and that board is reading batt level at A1 after the switching mosfet… I think… as ADC_IN to its S3FN8 at GPIO1. And looking further it seems that pin functions are swapped when comparing Heltec V3 to Xiao S3. Does firmware determine what functions these pins serve at boot?

Edit: I tried starting up on the Meshtastic Discord and got the scariest looking Captcha ever seen, endless loop email verification…so given up on that.

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Hi there,

Yes I can verify it does work, ALL the more reason Seeed’s next Xiao should have a PMIC … period , in this day and age to not be able to accurately read the F’n State of charge of the battery, power-cell, nuclear-reactor or Solar connected to the SUN :sunglasses:, especially when you praport to be a battery powered wearable device solution . Give me a Break. It’s like rule 2 or 3, :face_with_hand_over_mouth: IDK go look it up.
Lucky we have users and fellow makers who take time to figure out solutions and provide them for nothing in return. You don’t have that in any other forum. MARK IT :point_up:

All that being said , it works using the Voltage divider, you do give up the GPIO is all. but that would be kinda the same as an INT pin required for a PMIC chip. You get SO much more… Hopefully the Next revision of the Expansion board will have a number of improvements and be usable for all the Xiao’s (even if it requires some jumpers IMO)
Noteworthy you can use the read battery in the older stuff and Non-mbed on the Xiao Directly so there’s that :laughing: Mod is good enough to get you going.

HTH

GL :slight_smile: PJ :v:

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