Teensy 4.0 board support

Apologies if this is the wrong venue to ask for board support, but I wanted to see if it would be possible to get Teensy 4.0 support added. It hasn’t officially released yet, but it looks like it’s going to be soon. Near the bottom of this page is some detail about the current status: PJRC (Teensy) Forum

The commits to the Teensy library are on Paul’s github as well, but I can’t link to it since I’m a new user.

I’ve really been enjoying using Platform.io, and I would love to be able to get my application on Teensy 4.0.

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On the github as an issue as you did here is generally the best place, then it serves as a bit of a todo list also :wink:

Just note that the general policy for Platform.io is for to not update to non-stable releases… it’s enough work for them as it is to support all the stable boards, and fix bugs, etc, without adding unstable and beta releases to the mix.

On a side note, thanks the heads up that there is a new board coming… I lost track of development in the Teensy world after 3.5/3.6 were released… Will have to investigate and see what new stuff Paul is adding to the mix! :smiley:

Edit: Jesus… it can be clocked up to 600Mhz??? What sort of microcontroller is this??? :open_mouth: :laughing:

Yes, that’s a good point about the beta status. Some of the initial development appears to have been done with the RT1052 chip, switching later to the RT1062, so yeah that could become confusing.

My goal really was to just start the discussion.

600MHz and 1MB of RAM, it will really open up some possibilities.

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Do they still plan to release it without debugger support (one of the biggest disadvantages of the current Teensies)?

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Best to ask directly. I don’t have one of the beta units, so I don’t really want to say one way or another in case it turns out to be incorrect.

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Released today: Teensy® 4.0

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Also on Sparkfun Product Showcase: Teensy 4.0 - YouTube Teensy 4.0 - DEV-15583 - SparkFun Electronics

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Thanks for the update! :slight_smile:

Saw it had been released about half an hour ago as Paul also posted an update for people who’s backed the Teensy 3.5/3.6 on Kickstarter… it looks like a big step up for MCUs… lots of speed, program memory, runtime memory, plenty of GPIOs, DMA, etc, etc… Hope it gets a good reception! :smiley:

Please install the latest version of Teensy dev/platform. There is support for Teensy 4.0.

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The Teensy 4.0 board is described with debugging capability, if J-LINK probe is used. Problem is that the JTAG ports are not exposed on that board, see e.g.


and another thread on that forum.

So JTAG/SWD debugging seems not to be possible.

Might be also a problem with Teensy 3.x description.

so, does ie means I cannot debug teensy4.0 board on platformio ?
which said

and JTAG/SWD can not be connected.

My understanding is that you cannot use J-Link if you do not modify the board itself. See also PJRC (Teensy) Forum for some “tips” from the creator of the board.


Paul S has said:

All Teensy 4.0 are fuse configured for JTAG signals, TCK,TMS,TDI,TDO, so plan on those 4 pins. SWD protocol using only 2 wires isn’t supported. The fuse setting is irreversible, so it’s impossible to use SWD.

And the catch is those four pins are ONLY connected to the MKL02Z32VFG4 chip that holds the bootloader for the Teensy4 (the reason it is basically unbrickable)… so yeah, it sounds like unless you want to start going to the fun of removing the main iMXRT1062 chip, and replacing it with one that hasn’t had SWD disabled, you may be out of luck. You can see on this thread where a few people have been scheming how to do debugging, and it’s not for the faint of heart, and there’s no success story there (yet?)…

lol… and I see @prismv posted the same thread while I was writing this! :laughing:


@prismv @pfeerick Thanks ,got it. As I just wanna make some simple applicaions , I will try more idea on solving code problems which may appear.reference PJRC (Teensy) Forum

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