Teensy 4.0 (hypothetical) pin assignments

Understood; it wouldn't be fair for someone to get one that didn't understand what is expected of them with regards to beta testing hardware like this.
 
I have multiple copies of the development environment installed on my linux box by having them under different user IDs. I need to do that because I'm working with three radically different controller boards that have conflicting setups in the development environment.
 
@Paul,
I understand that the pins for sdhc are already taken of pin list.
Q: will there be a on-board uSD (e.g. lower side?) or are there some pins/pads for external uSD?
 
Seems 180 of the removed pages are from table of contents, which was ridiculously long on Rev 1 due to fully expanding all the sub-sections. Doesn't look like they actually removed any significant info.

It's still filled with copy-paste errors from iMX6, like "the maximum chip supported frequency 1.0 GHz" which moved from page 411 to page 957. Still has lots of confusing stuff, like the SRC diagram (who draws such a stupid diagram?), which now appears on page 1242.

At least they changed to the sensible organization of chapters, rather than alphabetical by module acronym.
 
I read through a bunch of this. I can't use all the things the 3.2 already has by a long shot. I do love the SPI bus, analog is good. 5V tolerant ports is really a nice feature. And the other common stuff to make life easy to program it for the semi-lost people like me. 600 Mhz? Seems you could just code whatever's missing. I'd just really love it if it came out as a Faster, bigger RAM 3.2. Don't waste the space for the SD card reader. 9/10 time's I'd like that located elsewhere anyway.

P.S. Not all exited about the dedicated red LED. I'd happily loose it if you needed the space for other stuff.

-jim lee
 
@jim - … a bunch … only 233 prior posts [this thread] :) Like the T_3.6 - this high speed MCU won't have 5V tolerance. Beta boards will be going out when the next hurdles are in Paul's dust. One big one is the boot process as the chip has options/complexity that have to properly resolve in a way suitable for reliable Arduino user usage, the 'dedicated to the bootloader' red LED must have seemed worth the space/power/parts planned for it as all else for PCB space is likely allocated.
 
At this point, most hardware design decisions are set in stone (or FR4 fiberglass). However, which pins we'll sacrifice to get the CAN FD pins is still unresolved. The first beta will have the pinout of msg #181, using the older 1052 chip. That part is absolutely certain, because I have the first 14 boards sitting on my desk right now! More are scheduled to be soldered later today. My hope is we'll manage to start the beta next week with about 20 boards available, and probably 10 to 20 more after Christmas and into early January.

The 1st betas do have the red LED. It actually needs a little mod wire, due to a mistake on my part. Originally (on an earlier board rev) the red LED connected to GND. I moved it to one of the open-drain-only pins on the MKL02, but neglected to change the connection to 3.3V - so everyone who gets one of these 1st betas will see a little mod wire for the red LED.

I haven't really talked much about the rationale behind adding this part. The 2 immediate cases driving it are #1: the ongoing problems where people have a lot of trouble diagnosing why their computer doesn't recognize Teensy, ultimately due to a charge-only cable, and #2: the difficulty of using the 15 second button press to fully erase the flash memory.

I also have an optimistic (maybe too optimistic) very-long-term plan to someday support an alternate high-speed upload, where your program is up and running from ITCM while the data is still being written out to the flash. The MPU will prevent writes to the unsaved data (well, unless your code messes with the MPU). My hope is to pull this off without any USB disconnect for the common case of uploading again with the same USB Type selected. Ideally we'll be able to avoid the really slow (especially with Windows) USB enumeration entirely. Many details to be figured out...but I'm pretty sure we're going to depend greatly on the red LED for visual feedback. This overly ambitious dream of full upload & software emulated reboot measured in only milliseconds, without any USB enumeration, is a big part my personal motivation for the extra LED.
 
Ha ha! Sorry, late to the party. I'm fine with the LED. The 5V thing, is it the chip on the teensy that allows this? Or is it hardware you put with the chip?

And the big question.. Will this new machine be able to drive the data line on a string of NeoPixles directly?

-jim lee
 
jim lee said:
And the big question.. Will this new machine be able to drive the data line on a string of NeoPixles directly?
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WorldSemi recently announced all new WS2812 will be compatible with 3.3V signals.

So yes, in the future they will all work with every Teensy and the many other boards on the market using 3.3V. Almost nothing uses 5V logic these days.
 
PaulStoffregen said:
WorldSemi recently announced all new WS2812 will be compatible with 3.3V signals.

So yes, in the future they will all work with every Teensy and the many other boards on the market using 3.3V. Almost nothing uses 5V logic these days.
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Yeah. Of course there is all of the existing stock both in people's hands, and sitting in warehouses waiting to be sold. Hopefully the SK6812's will also be all 3.3v. IIRC a Teensy can probably only drive 50-100 LEDs using the 3.3v power line (I have driven 16 or 32 LEDs on my neopixel rings that can run at 3.3v, but I take care in the code never to use more than 150mA if I'm using two 16 LED rings).

As a coincidence, I was just looking at replenishing my supply of neopixel rings today and looking at various prices. I have had some clone ws2812b's that didn't work too well.

I do wonder when the general move to 1.8v will begin in earnest for the hobbiest market.
 
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I can attest that a teensy 3.2 can drive 150 NP strip. No problem so far.

That's what's on the front of my truck. :)

I'll shut up now, sorry to drag this off topic.

-jim lee
 
jim lee said:
I can attest that a teensy 3.2 can drive 150 NP strip. No problem so far.

That's what's on the front of my truck. :)

I'll shut up now, sorry to drag this off topic.

-jim lee
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Just to be clear, I meant assuming that the ws2812bs are powered by the 3.3v pin from the Teensy (and not from VIN or an independent power source). There you have perhaps 500mA of power from a Teensy 3.x and 300-something from a Teensy LC. Which is enough for 8 ws2812B at full white power (60mA). I limit my ws2812b's to a max of 30 for the sum of R+G+B, and that is roughly 75mA for a 16 LED ring or 150mA for a pair of rings. I would assume you are powering the ws2812b LEDs from VIN and not from the 3.3v power line.

Obviously people have built displays with thousands of LEDs, but there you have to start worrying about how to power the display more carefully than if you just add a ring or two to a costume.
 
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