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Comment by filterfiber | Hacker News Reader

This is an excellent write up!

> Seeed Studio XIAO ESP32S3/C3, WaveShare ESP32S3 Zero, Unbranded ESP32-WROOM with OLED, Orange Pi Zero W (untouched), Raspberry Pi Zero W (L->R, T->D) After testing all of these, the only one reliable to work for long periods of time (one month currently) was the XIAO ESP32C3/S3.

I suspect they may be having power issues? For the ESP32's specifically I highly recommend adding a beefy capacitor over the power rails, as those can be rather sensitive to voltage fluctuations especially when transmitting. Both the RPi and ESP's can be finicky depending on the power supply/cable/cable length too, and the RPi's sdcard does tend to fail from sudden power loss. They should all be capable of at least a month, my pi's and esp's have gone several months.

I'd be curious to see the results from other ESP32's (or even the pi) with a larger capacitor added.

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It’s definitely not a reliability issue, with the platform - ESP32 in general is very popular so it’s surely an issue with my usage. I’m fairly certain it’s just a cheap manufacturer issue I ran into. I bought essentially a no-name ESP32 at first and that’s the one that refused to last. Proper manufacturer solved that issue for me and now ESP32 works just fine.

The raspberry pi actually never worked, largely because I tried to shoehorn way too much complexity in and manage too many things. It’s just a BT scan and a HTTP call.

I don’t think it’s a power issue as it’s getting 5V1A from a power outlet directly to USB-C into the device. Though that’s definitely something I need to look into, as the Xiao ESP32-S3 I have also had intermittent issues, and IIRC the XTensa cores are more power-hungry than its RISC-V based sibling, the ESP32-C3.

> I don’t think it’s a power issue as it’s getting 5V1A from a power outlet directly to USB-C into the device.

It's not the total voltage/wattage the PSU can provide, but the voltage at the processor.

The ESP's varying current draw notoriously causes too much noise and a lot of boards don't have large enough decoupling capacitors so the voltage drops too much and it glitches out. Also a warning that USB PSU's can very MASSIVELY in quality (I'd suggest an apple one for testing if you have one handy).

I think you're right that the RISC-V processor is either better behaved and draws power more consistently, or the board has shorter traces to it's bypass capacitor or a larger bypass capacitor.

This is correct, I thought it wasn't and was going crazy trying to debug my Pi 3 resetting my 3D printer every time, with any of ten power supplies I tried, including a configurable bench PSU.

I switched to the official Pi PSU after someone said "trust me on this" online, and yep, zero issues in all the years since.

It's voltage for Pi 3. They forgot to account for voltage drop due to protection or something. Official as well as third-party Pi 3 specific adapters are rated at 5.1V to mitigate that problem.

Early alexa devices also have power supplies that are rated at 5.2V, those could be an alternative. I also had a good experience with a 30W oneplus warp charger after some power issues with cheap 5V2A ones.

>don't have large enough decoupling capacitors

Is this something you can eyeball to guess at quality?

Are you sure that the system isn't still running, but it has just disconnected from wifi and is failing to reconnect? I have a few status LED's flashing to show the main CPU is still running, and it often is, even when the device has fallen off the network.

I find that happens fairly frequently unfortunately, and haven't managed to track down the cause.

Hm, that’s a good call. I have a callback on the connection dropped to reconnect but it’s possible it needs a full reboot? I’m going to have to sit in on the serial monitor and wait until something happens and see. Thanks for the tip!

I live in a very wifi-busy area (hundreds of networks), and I suspect that the wifi logic somehow hangs itself waiting for some packet/message/state which gets lost and never comes.

I chased a reliability problem with an RPi3 for a while before figuring out it was a poor quality USB cable that I was using for power.

Not saying that’s your issue obviously, but I spent a couple more hours than I really should have swapping USB power bricks but not the cable (because it was threaded through the printer enclosure and laziness prevailed).

I didn’t consider that as highly as the outlet adapter since that’s what pushes the amperage and wattage, but thanks, I’ll definitely be investigating that next!

I've found cable quality to be quite important for Raspberry Pi, particularly if you're not using an official adapter, the head room can be low and the resistance of the cable can tip it over.

I haven't had major issues with ESP devices but I try to keep them on <30cm cables of decent quality and ensure they're shielded. Though I haven't tested experimentally, I'd expect low quality, poorly shielded cables to have some effect on the signal quality.

Just put a huge low-ESR cap on the 3V3 rail. Newer WiSoCs like ESP32 draws too much for too short that regulators can't catch up. I've once had brownouts with an Uno R3 style ESP32 board, and it didn't stop until I added a 0.22F EDLC from my junk bin, which is absurd and not a recommended usage of EDLC, but I think even 330uF electrolytic from same bin didn't cut it.

I have a bunch of ESP32s performing critical-infrastructure tasks in my Home Automation; they've been running flawlessly for about a year now; I update them occasionally (ESPHome) but haven't had any issues.

Some of them perform multiple tasks, e.g. one of them is Bluetooth proxy in my home office, but it also runs the light strip along my Skadis wall boards.

I'm using some random brand ones from a company called "AZDelivery" on Amazon.

I haven't done anything special to them; they sit in 3D printed cases, and are plugged in with relatively short cables (usually <30cm where outlets allow) into at least 5V/1A adapters.

I have a number of similar devices but I use dirt cheap Wemos D1 Mini boards from Aliexpress, they usually cost around a buck each (and they come in ESP8266 and ESP32 variants).

I'm a huge fan of using Alpine with the RPi due to reducing writes to the SDCard. it will only save data to disk with a lbu commit -d and by default boots into a kind of tempfs.

I have been using Alpine for a while but didn't know this!

At the moment, I'm looking for a way to make my storage more resilient on a Pi I'm using to host Hashicorp Vault, for secrets in Filesystem mode.

First I looked at high-resilience SD cards, but I don't really want them stored on the OS card anyway, also considered just getting a high-quality USB stick and mounting the secrets storage to that; It sounds like a combination of one of these (or perhaps another, similar option) alongside Alpine to reduce writes to the OS SD could be the ticket.

I have a couple of Pis on my network edge running things like WireGuard, with the root mounted read-only to try and help with the issue of SD card resilience; I've killed dozens upon dozens of SD cards in Pis over the years.

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