So Mitch (FluidNC) took the time to work me through some Oscilloscope tests.
We have had some issues with the import esp32 boards.
1- The USB-C versions are missing a capacitor or it has the wrong value. This causes the bootloader button needing to be pressed. That has a warning in the FluidNC web installer now. So not too bad.
2- The micro USB versions do not reset the way they are supposed to. Turns out they are missing or have the wrong value pull-up resistor. They still work but not as quickly as they could during flashing only.
I have sent all the data to the manufacturer, I am not holding out for a fix but I figured this might help down the road.
The Genuine ESP32-DEVKITC-32E is about $6.70 more per board.
All the esp’s I have do currently work. Should I offer a genuine as an option with the premium price?
As a non-geek who doesn’t speak very much techno babble (and I think there are a lot like this particularly starting out) I would prefer something that “just works” and not to have to worry about capacitor values or pull-up resistors.
Currently, they all work just fine. Just hard to push the price up 3x on the ESP, so I think offering it as an option is a good plan to start with. I will let people vote with their wallet I guess.
I was planning on dropping in a bunch of details but that is not fun. I guess I should, though…
1- The USB-C versions seem to have something going on with the boot loader pins.
A 0.1uF capacitor between the ground and enable pins makes it behave as it should, without it, you need to hold the little button down when you flash it to enter bootloader mode.
2- The MicroUSB versions actually have a bootloader lag and do not reset as they should. They still work fine but they would flash faster and the web installer reset do not work as they should. Settings changes should always have a power cycle so no day to day issues either.
A 10k resistor pull-up from 3.3 to gpio-0 makes these function as they should
I have a feeling this is going to be a chronic problem where these ESP32 boards are “good enough” for a hobbyist with workarounds, but known-good ones might be simply unavailable. You can’t get a known-good RAMPS board even if you pay more. And 608 bearings are a crap-shoot on Amazon (regardless of price) and you have to go to a known supplier to get good ones.
Maybe a long term plan could be to transition to on-board ESP32 modules and drivers like the Fysetc E4, but with six drivers. Maybe the cost savings of the sockets would offset the cost of having the 6th driver populated.
You could make these so they are 100% hardware and software compatible, just a different form factor. I’m not sure if the board size can be kept the same.
I did end up looking at that, the difference was $1.80 for genuine modules and the whole devkit (not including the extra cost of adding the other components from the devkit to the board). Adding the module and components to the board would also increase it’s size a bit. I am not completely against it though.
I did find another esp supplier, ordered some samples to see if they are any different.
The current supplier got back to me, the reply was off-topic and seems to be lost on the sales rep. I reworded it.
Espressif also got back to me, but not with any bulk pricing numbers…yet.
Thank you for taking the time to document this.
I see it as an errata note that should be somewhere in the documentation.
I’d see this as just something to go fix if I happened to have one of the bad modules.
Others might not want to deal with it.
I wonder if this is why I had a couple of funny flash runs on the Jackpot I have on my JL1 Laser. Once flashed, it hasn’t had any issues. Mine is the microUSB version.
Up to you. I consider it very valuable to have a credible source of genuine parts. I’d buy a couple of known genuine USB-C boards from you right now if they were in the shop. But it might be a distraction and not very lucrative for you so may not be worth YOUR time.
I’m really happy you put the details here along with pictures of the fixes.
There’s a lot of value in dealing with an open supplier aside the question of genuine vs clone.
Thinking about it…since I can make board edits. I can add a couple extra hole to account for anyone wanting to add either fix. Drop in a through hole, quick solder…Gotta think about that one. Like having this kind of control over a board design!!!
The genuine and knock off prices are both very inexpensive. The fact that they start at $2 and end at $6 make them bith a great deal. Thinking of it as 3x the price makes it seem crazy. But $4 more is not a huge leap. Think of it in a kit. $300 vs $305 is insignificant.
If you are flashing them and doing any kind of testing, that is worth a lot more. If you are doing RMAs and support, that also should being up the price. You used to sell ramps for much more than Amazon and it was well worth it. $20 vs $45 seems like a big markup, but add it to the total cost of the CNC and people will gladly pay for the smoother experience.
Some people will still gawk at the price and want to save the money (that’s totally fine). They can easily source it themselves or buy your as-is stock and have to push the button to flash or reset it.
I haven’t started a build yet but as a newb trying to learn the details here, I would 100% prefer to pay $9 more and have a genuine control board that is free of the minor faults.
Ryan, appreciate your honesty in showing the lower cost option but it is a YES from me for a genuine board.
I am waiting to hear back from espressif, three emails back and forth and no prices yet…but they have said they offer bulk prices. So fingers crossed.
Make it $70 and buy an extra coffee a few times a week.
I mean, heck… I pay more than that each month for youtube tv just to watch college football… And that gives me way more anxiety than flashing a Esp32 board.
I could look at my espixelstick board to see what brand Esp32 it’s using. I’ve had 0 issues with those.
Well in a giant bulk order it knocks off about$1.30 each. 6-8 weeks lead time. That is pretty brutal and would tie up a lot of money.
JLCPCB SMT Parts Library & Component Sourcing the price of the genuine modules is better than I remember. Making our own devkits might come out to less than bulk, and in smaller quantities with much shorter lead times. That would have a genuine chip and components and a layout we control. I will look into this further.
