Remember too, you’re not designing flight hardware or spaceships. So some errors or dead boards due to emi can be tolerated. If someone plugs their 220VAC into the ethernet port, it’s ok for the jackpot to go belly up.
These kinds of input protections are really just to make it hard to use the wrong way and easy to use it the right way. Or to keep a common mistake from causing a ruined weekend.
ESD protection on an external interface to a hand held device that WILL be used in a high ESD environment is hardly anywhere near something flight rated.
I get where you’re coming from, but strongly disagree with the hyperbole used to make that point.
This is more akin to ‘bare minimum needed to not look utterly ridiculous to anyone who knows what they’re doing’.
The design of Jackpot V2 looks nothing like flight hardware.
But I think Jeff is relating a lesson I have to think about all the time: perfect is the enemy of good enough.
I don’t mind Jeff pointing it out, because I certainly do spend time in a world where we’ll spend an extra $100,000 per system to take a working design and make it just a little bit closer to ‘perfect’.
This is very true.
But, Jackpot V2 is an integrated board- so you want to at least try and avoid someone ruining a $75 or $100 board because they did a common thing like plug in a pendant connector that they handled with their thumb or accidentally unplugged or plugged in at the wrong time.
In the ecosystem, the other sibling board designers have reported they get notably less returns with their admittedly non-ideal protections. That’s probably the right level of effort, and Ryan working to make his board just a bit better is typical Ryan.
What I’ve seen in the thread above for the new design looks like it’s going to be the right compromise between perfect (Impossible) and nothing at all. Said differently, good enough. I think the Jackpot V2 is going to prove to be better than good enough. That’s what Ryan has said he’s shooting for- and I think he’s got it.
Yes, this. What Ryan’s designed above doesn’t look utterly ridiculous to me and in fact looks reasonably good for an inexpensive design.
It’s got a reasonable ESD protection, series protection resistors, an appropriate looking amount of capacitance in the right places for the interface.
It doesn’t look like it will cause problems for a 1Mbps serial interface, and it shouldn’t get in the way of using the expansion header in the normal way.
I’m chomping at the bit to get my hands on this next iteration and put it through its paces.
Hook it up to M5 and CYD pendants, an Airedale, a 0-10V spindle expansion module, and whatever else I can dream up to trial run with it.
Exactly.
Sorry for the offense. I don’t know enough about the parts you’re jointly designing to know how much hyperbole that was. I was just pointing out that the level of effort needs to handle the level of risk. At one extreme is the stuff Jim works on, where you have to spend millions and wait years before shipping a replacement. Or on a passenger plane. At the other extreme is the hobby boards I’ve made that have zero protection.
Boards like RAMPS had no protection on the screen or otherwise, except they were designed to not have a problem if you swapped the plugs around 180. I don’t want to go back to that level of quality (it was poor for other reasons). But it can be hard to know where to stop.
Come on, not you as well… 
But it looks great, it is going to be an awesome board! 
Why not just make the board an inch bigger? Is this like the optimal size for paneling or something?
Then you can have even more cooper for cooling
NEVER!!! Most efficient package! I just can’t bring myself to make it bigger if I can make it fit.
If we add more room you guys will want more stuff built in…
Thanks, I appreciate it. It was a knee-jerk reaction on my part and not really helpful.
If we don’t know failure rates then we can’t draw conclusions from that, though. That’s maybe my main issue here. There are tons of people who have had weird issues with Arduinos and stuff over the years. It’s not uncommon to see forum threads where people say their board isn’t working right and eventually either give up and stop responding or replace it with a new one and it works again. All of those can be some form of damage that’s occurring that could be easily prevented.
Even if Ryan isn’t getting RMAs for those because people think that they’re the ones that damaged the board, that’s still someone who is now out the cost of a replacement board at minimum or who has been left with a negative impression of the board or machine. Those kinda things add up. Losses in confidence with a product due to EMC issues has killed some pretty big companies over the years. Even just the time taken to respond to forum comments trying to figure out an issue have costs associated. Over the lifespan of a couple thousand units, the cost of a single issue outweighs the components we’ve just added to prevent it.
That’s also using an entirely different microcontroller, the Atmel micros are well known for being extremely robust. I’ve had very few fail for any reason despite using them for nearly 10 years as our standard range of microcontrollers and in some pretty nasty conditions. I’ve had maybe a ~10-20% failure rate with ESP32s just mucking around with them at home. I still wouldn’t allow exposed unprotected GPIOs in any design I did, but I’d definitely be less concerned about that situation.
Always more never second best 
You always need to make the decisions that are best for the business
Arduino i have stuck 3 with a screwdriver had one absorb a adult beverage and two surcome to lightning. 100 year old house with 50/50 original wire not all just enough. Funny i think im using the original drivers still thought
I took a bit of a journey down a rabbit hole.
@jeffeb3 loaned me a thermal camera, and I happily went to throw it on the one android phone I have, which is a backup for when I travel.
That old clunker didn’t have a USB-C port and I didn’t want to start making an OTG+adapter cable+hand managed external camera.
So it turned into research on what affordable, 5g, Android, mediaTek, unlocked phones there are.
That took days longer than I intended.
Result: some jackpot V2 thermal pics.
This is on the JL1. Not a stressing application. Today was cool unlike the days this week which were up around 100F. It gets to 112F in the garage. No PLA sagging now for several years these machines have been in there.
I managed to get some tiny SMT resistors removed on the board I am modifying but still need to add the different parts back on.
My eyes, hands, and eye/hand coordination aren’t what they used to be. Don’t get old!!
Those suckers are tiny!
This board doesn’t have the better connectors that Ryan found for the release boards.
And I’m still learning how to drive the camera app. Don’t trust any numbers.
Have you got a viewer or microscope? That and reorienting the board so you can keep as much of your hand touching the benchtop are what works for me for real small stuff, although I’m still at the point where I can work down to 0603 without magnification.
I’ve tried using the hobby magnifier style and can’t stand them. The visor types are ok but I found those frustrating for going back and forth. A magnifying viewer like the Mantis range are good if you can find a 2nd hand one, but I honestly prefer my cheap binocular microscope on its lowest magnification.
Nice, that camera has much better resolution!
Argh. I didn’t even think about that. I hope you didn’t spend to much on a burner phone. The camera itself was not that expensive.
Why were u removing them?
A component change happened in the design, no reason to trash an otherwise perfectly functional board- so I’m reworking it.
Found a really good deal on a better spec than I thought I’d find , and will get to test a mediaTek 5g chipset - which was already on my to-do list.
Though, I may now have to buy one of these cameras for my iPhone- and sadly the iPhone and Android cameras are different. I’m going to wait till I have a chance to look in the one place my camera may be.
I have the FLIR camera that plugs into iPhone, with the lightning connector. Now I have a new iPhone with a usb-c connector 
