Is there a market for a Teensy 3.1 48 pin ARM stamp?

Status
Not open for further replies.

t3andy

Well-known member
For $12 more, I can purchase a Teensy 3.1 breakout from Tindie which breaks out all the GPIO but adds layers of unnecessary connection points. (no offense talldog)

Why not just redesign (PJRC), from scratch, a "clean" 48 pin Teensy ARM stamp and be done with it? I really don't believe it would cost $14.50 extra to produce it.
The extra cost would not be that great and would be very convenient for GPIO power users.
:cool:
 
Last edited:
There is a thread on planning for a new Teensy 3.x++ with a hotter MCU that will be larger with more pins like the T_2++.

I agree though - PJRC making a large format proto version - not so big as an UNO but more accessible would seem nice. Maybe put a high density plug on it to keep the Teensy 3.x++ itself smaller - but allow pulling out those pins to a larger board. Of course the plug would add $ to each, even if it fit on the extended PCB.
 
Technically, there's nothing really stopping anyone else from making one - as long as you get the MINI54 (or whatever the replacement one is going to be in a few months) from PJRC. I've built a custom PCB (actually at this point I've made about 16-20 of them) with two 'teensy' sections on it.

I'd just wonder if it's worth the time and effort put into it, as it's only cost effective (especially with the added cost of the pre-programmed bootloader chips) if you make a LOT of them at a pass - and it seems like the regular Teensy 3.1 is enough for the majority of people.

Basically, I don't think there's enough of a market for redesigning the 3.1 to cover the cost of the redesign/make a profit.
 
Basically, I don't think there's enough of a market for redesigning the 3.1 to cover the cost of the redesign/make a profit.

Only PJRC knows this answer but it's a shame to cost the end user lots of money to access the extra GPIO on the bottom of the Teensy 3.1. At the time, Paul S. was under the gun with Kickstarter to produce and ship a product on-time. I believe (IMHO) many users will "pay up" a few dollars for easy access of the extra bottom GPIO! Right now, buying the Tindie solution is OK but really a solution from Paul S. would help with the bottom line of PJRC. After all, PJRC is a commercial enterprise and most companies listen to the wishes of their users/customers.
:cool:
 
Last edited:
Only PJRC knows this answer but it's a shame to cost the end user lots of money to access the extra GPIO on the bottom of the Teensy 3.1.

Well, its pretty easy (and cheap) to access the bottom pads: Solder wires to it. I can't see any costs..
I'm soldering the pinheaders anyway, so thats no burden.
But, to be honest: I needed these bottom-pads only one time (two of them).
 
From PJRC's perspective (I'm assuming a lot of things here) it probably makes more sense to focus on the ++3.1, as opposed to devoting development time to the 3.1. As a power user myself, I would probably rather have a fully broken out ++ 3.1 compared to a fully broken out 3.1 - there's already workable solutions for the 3.1 being broken out, and redesigning it would probably cannibalize sales from the regular 3.1. The ++3.1 would then take longer to release - Paul only has so much time to do things!

I doubt we'll see a fully broken out regular 3.1 from PJRC before the ++3.1 comes out, which is why I think the only way it'll happen is if someone else handles all the board design and development (honestly I'd be up for doing this). The problem with someone else handling it is that the cost of the pre-programmed bootloader chip from PJRC becomes at least mildly prohibitively expensive ($5-$8 per board just for that one chip).
 
Here's several replies, rolled into 1 message....

I'd just wonder if it's worth the time and effort put into it, as it's only cost effective (especially with the added cost of the pre-programmed bootloader chips) if you make a LOT of them at a pass - and it seems like the regular Teensy 3.1 is enough for the majority of people.

This is exactly my thinking, except we program the mini54 chip.

It easy to say "just redesign ... and be done with it".

The actual engineering doesn't take too long, maybe a few days to lay out the PCB and build/test it. But when you add on building a new bed-of-nails test fixture, ordering PCBs and scheduling production of product, increasing the ongoing complexity of scheduling parts far in advance so no Teensy goes out of stock, and lots of other little behind-the-scenes things that all have to happen correctly... it's quite a bit more involved then "and be done with it". It's all do-able, but it adds up to quite a lot of work.

I think ongoing product manufacturing, from forecasting sales to purchasing to inventory management to actual production to testing & packaging to actual shipping as sort of an art form. Much like olympic figure skating, done flawlessly, it looks easy. What you don't see is an incredible around of unglamorous hard work. It's very tricky to get right. If you look around most of the hobbyist hardware market, lots of products go out of stock regularly. Robin and I are actually pretty good at it... but I can assure you, that's not some effortless natural talent. It's a lot of work to do well.

The 2 biggest concerns are the financial investment to make large enough batches for Teensy's normal low pricing (on a model that's unlikely to sell much), and spending time working on this, rather than things many people want much, much more... like a debug version and a ++ board with that new 180 MHz part and new USB types and about 100 feature requests on the audio library and adding write support to the improved SD library and a biopotential sensor library and setting up a wiki and someday even putting serious work into really improving the website. Time is the really precious, limited resource. Releasing any new product, even something seemingly simple, uses up quite a lot of time that necessarily delays other stuff.

After all, PJRC is a commercial enterprise and most companies listen to the wishes of their users/customers.
:cool:

I sure do try to listen. The hard part is fitting the massive number of very different requests into a fixed number of hours per day. Only a small fraction of things everyone wants can get done. I have to (try to) choose wisely.

But, to be honest: I needed these bottom-pads only one time (two of them).

This is also a pretty common response I hear. This, and that it's less convenient but still not too difficult to get to those bottom side pads when necessary.

From PJRC's perspective (I'm assuming a lot of things here) it probably makes more sense to focus on the ++3.1, as opposed to devoting development time to the 3.1.

So far, this has been my plan. Well, and a debug version. At this point, real debug capability is by far the most commonly requested feature.
 
Last edited:
When PJRC has the ++3.1 plans up in hand it would be worth considering an alternate PCB of the Mega type exposing the extra pins - that might add $5-10 due to lower build rate and more materials? At which point you have RasPi pricing, but it would be better than buying the Teensy then dedicating it to a $12 add on board that almost gave you the same end only now two boards thick and out of warranty.

As noted maybe a fine pitch connector that exposed 10+ extra pins to a connector or cable to a secondary board that could fit in a small space.
CheapDuino.jpg
These AVR's build in china for $4 each - with a 10 position ribbon. Would take a deft hand to solder if not factory installed up top on the extended ++3.1 end space.
perhaps a $1 connector type not ribbon - like this: http://www.anglia.com/hirose/datasheets/e68700015.pdf
 
Hey Paul, would it be very hard against your grain to lay out the Teensy 3.1 circuit in the much sought after 48 pin footprint and then just build one or two to test, no bed of nails, not that great a burden on PJRC resources - post the board on OSH Park (or where-ever that was I saw a lovely little collection of boards offered via them from you) and (perhaps) offer to sell a set of components required?

Keeping it to just rerouting the 3.1 to the larger footprint would (hopefully) aid in both making it quicker/easier to do and in not needing to find stock of whatever this or that new components - it may even be possible to lay out in such a way as to work with the existing bed of nails if it can allow the new real estate to just poke out at that end.

A bit unfriendly to lesser skilled & tooled people but I am willing to bet that most people bugging you for the Teensy ++ 3.1 are reasonably capable and this could be a comfortable enough (for most parties) way of cutting to the chase for this one; hopefully not much time needed on it so you can get back to concentrating on the next generation Teensy you really had in mind and that wiki I'm about to return to my experiments regarding.
 
would it be very hard against your grain to lay out the Teensy 3.1 circuit in the much sought after 48 pin footprint and then just build one or two to test

You don't need me for this. You can do it yourself. Anyone can! Well, anyone competent with PCB layout software and fine pitch soldering. Admittedly, this isn't exactly a beginner-level Eagle project, but it's far from impossible.

All you need to do is lay out a Teensy 3.1 based on the schematic, in 48 pin or whatever form factor you want. Then buy the Mini54 chip from PJRC and the rest of the parts from your favorite electronic component distributors. Solder it all together and test.

If it's "not that great a burden on PJRC resources", certainly you or someone good with PCB layout could do it easily, right?
 
Hey Paul, would it be very hard against your grain to lay out the Teensy 3.1 circuit in the much sought after 48 pin footprint and then just build one or two to test......and (perhaps) offer to sell a set of components required?....
A bit unfriendly to lesser skilled & tooled people

Isn't this "not ideal, bit of work and extra cost" solution fairly well served by the breakout board already? Without chewing up PJRC time?

you can buy this and put it together in about 15 minutes:
https://www.tindie.com/products/loglow/teensy-31-breakout/


if thats too expensive, then Frank B showed an excellent, basically free method of flipping the Teensy and accessing the pads.

I can't see what would be achieved, forgive me if I'm missing something.
 
However, I will share with you 2 test versions of Teensy 3.1, using the larger TQFP version of the Mini54 chip and all pins routed to the outside edge.

https://www.oshpark.com/shared_projects/begoxVNS

https://www.oshpark.com/shared_projects/s82E93Gi

These come with ABSOLUTELY NO SUPPORT. I will not answer questions, not even which part is which. You're on your own if you try to use these. But I will at least confirm both worked when I used them for early development on Teensy.
 
@Pensive: I don't really appreciate you quoting me this time.

Isn't this "not ideal, bit of work and extra cost" solution fairly well served by the breakout board already? Without chewing up PJRC time?

you can buy this and put it together in about 15 minutes:
https://www.tindie.com/products/loglow/teensy-31-breakout/


if thats too expensive, then Frank B showed an excellent, basically free method of flipping the Teensy and accessing the pads.

I can't see what would be achieved, forgive me if I'm missing something.

Forgiven, but look:
For $12 more, I can purchase a Teensy 3.1 breakout from Tindie which breaks out all the GPIO but adds layers of unnecessary connection points. (no offense talldog)

Why not just redesign (PJRC), from scratch, a "clean" 48 pin Teensy ARM stamp and be done with it? I really don't believe it would cost $14.50 extra to produce it.
The extra cost would not be that great and would be very convenient for GPIO power users.
:cool:
I don't even want one or I would already have one - although I probably would have some pads towards the far end that I didn't end up routing because I couldn't decide which pins Paul had to leave behind when he settled on Teensy 3.1 designs which are the most valuable to break out if you can.
 
OK, sorry for quoting you robsoles, although I had seen that btw.

Still not convinced a custom/new small quant board is a marked improvement on general robustness/reliability over hard soldering to the pins on a flipped standard teensy. But that's just me.

As a customer of Tall Dog for this breakout product I'd still rather see the bigger beefier 48pin product than a 48pin 3.1 ;)
 
actually, sorry for being snotty about it, I could have rebutted without being so uncool, reasonably sure.

I'd prefer Paul got to spend as much time as he'd really like to next gen Teensy too.
 
Just make it yourself. It's not that hard and you learn a thing or two about Teensy's along the way.

With the QFP5x5mm bootloader chip you can do the Teensy layout in 2 layers without vias. Granted, it likely would be a bit wider and the pins won't be aligned pretty like Pauls Teensy 3.x layout (you'd need a 4-layer board for that) but it can be done at a relatively low cost. Stencils from Polulu aren't much either and they allow you to make more than a few. Plus add features you want from the outset, like provisions for a optional Yamaichi PJS0008 Micro-SD card connector or a Tag-Connect debugger port, for example. From my perspective, Paul has given anyone who wants to make the device all the tools they need, from schematics, to the bootloading chip itself. If this is such a burning opportunity, well then take the plunge! ;)

Paul has more than enough to keep him busy. I'd prefer he work on the software and hardware required to extend the Teensy line with new processors and software libraries.
 
Last edited:
There you go ... if any user steps forward and produces a larger 48 + pin version of the Teensy 3.1, then I would be the first to purchase your design if the price was reasonable!
:)
 
Mikroelectronica has nice hardware aimed at education. There compilers are not at all what I can use; The could have used GCC. But they sell compilers to universities too.
I've used GCC to write C++ code and load it to their boards using a $25 SWD pod w/debugger, rather than USB.

This board might inspire a similar idea for Teensy 3.2? that is of the same concept. The bus socket on the board is unique to them but they open-sourced the pinning and encourage its use on other products.
they have a dozen or so plugin/stackable boards - sensors, communications, LAN, wireless, battery, etc.

Is this a good scheme for a T3.2?++ that is easily expandable with a defined add-on card bus? (Not proposing Arduino's bus - too AVR specific). It seems that any future Teensy will be NXP/Freescale. The board below is not, but something akin could use a Freescale M4 or better with the T3 libraries.

http://microcontrollershop.com/product_info.php?products_id=6915
 
Last edited:
That would mean to make it incompatible to all teensy extensions....

If you mean teensyduino, I'd think such a board would stay compatible as it uses a compatible Freescale MCU, or a newer superset.
An expansion bus is sorely needed to standardize. And not the AVR-centric Arduino bus.
The bus on that Mikroelectronica board is apparently not intended to be very verstatile in stacking boards. E.g., there's only one CS signal. No GPIOs. So the bus pin count is too low and a teensy version could fix that.
 
I believe Onehorse will appear any moment, begging to differ about how many add-on boards exist.

Sure, there's only a few from PJRC. The same is true for Arduino shields actually from Arduino. Really, my intention it to let others build lots of interesting add-ons rather than trying to make everything.
 
Status
Not open for further replies.
Back
Top