Bootloader Chip For Teensy 4.0


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Admin Update:

T4 Bootloader Chips are now available.


Will the bootloader chip for the Teensy 4.0 be available for purchase? So I can integrate a Teensy 4.0 directly onto my pcb. I know you can purchase the Teensy 3 bootloader chips but I didn’t see the Teensy 4.0 chip on the website.
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At some point the bootloader chip in use that is common to other Teensy models will most likely be released with support for the Teensy 4.0 MCU as well. Paul has not posted anything to the contrary AFAIK

No idea what the schedule for that may be going forward - but looking back Paul has been fully occupied with PJRC matters like stocking the T4 and other models as well as software for T4 and TeensyDuino update to the IDE 1.8.10 and SerMon support to be generally usable as Serial monitor to the output rate from the T4's 480 Mbps USB.
PJRC will sell a boot loader chip for 4.0, but probably not until at least mid-2020, maybe later.

Teensy 4.0's bootloader as it exists today does not work with a fresh IMXRT1062 chip, so we can't simply sell you chips with the exact code we're shipping now. That code depends on the 1062's fuses being pre-set by the test fixture we use.

Eventually I will add code to the bootloader to detect a fresh IMXRT1062 chip and automatically set its fuses. But today that code simply does not exist. And *many* other things, like adding the missing USB device types, are a much higher priority, so you can expect this bootloader work to not happen until at least the middle of next year.
Quick update, if anyone's still watching this thread... today I am working on making the bootloader compatible with virgin IMXRT chips (the chip on Teensy 4.0 gets fuses initialized by our bed-of-nails test fixture).

Bootloaders need to be tested very thoroughly. We'll probably have 1 month or longer of testing, so please do not expect to see PJRC offering a ready-to-use bootloader chip until March or perhaps April. But it is coming.
Definitely looking forward to this! Paul, will you be making an announcement when the new bootloader is available?
Hi, I'm wondering if there have been updates on the topic? Will a ready-to-use chip be made available in the upcoming weeks in PJRC? Eagerly looking forward to this!
I can confirm that I have, as part of the work towards Teensy 4.1, updated the bootloader to detect a virgin IMXRT chip and initialize it. So the major blocking issue has been solved.

Much work and careful testing remains to be done before PJRC can sell this as a stand-alone chip. I hope you can understand how bootloader code requires much more testing than regular software.

I can not give you a time frame, especially during this time where PJRC is running short staffed due to Oregon's shelter-in-place order for Covid-19. But I can tell you that work will not even begin until we're shipping Teensy 4.1 and Teensyduino 1.52 is released. A couple weeks after both of those have events have happened would be a good moment to ask again about this chip.
I know your still busy with the shelter in place still going on. Just a reminder we are still patiently waiting for this.

I would also buy a few chips. I have 3 Teensy 4s that I managed to burn the chip. So hopefuly I will manage to replace them.
We use Teensy as a basis for commercial products and have implemented T3.2 and T3.6 (laying it out now). What a wonderful way to accelerate development, and we really appreciate the hard work that has gone into the software base and contributions from the extended team of users. We are happy to pay for a programmed bootloader to support PJRC and contribute any enhancements back to the code base. We've already bought a couple thousand MKL04s.

We are looking forward to some new products that will require the performance and features of the T4.x, but that BGA is pretty intimidating to layout. Fortunately we have friends that can help, though we'd rather not have to do it. An alternative would be a "compute module" form factor Teensy 4.1. Either a SIMM connector, or maybe a M.2 Socket 3 connector. They can be had in 67 position, if that is enough. In any case, the goal being to fit the Teensy into a space under the main PCB where a socketed Teensy won't fit without making the enclosure form factor thicker, which wouldn't look good. A through hole socket would be a problem too, where a SMD connector would not interfere with parts on the top of the PCB.
In this form factor, we would like the SD card pins to the edge connector and not populated on the Teensy. The Teensy could be larger and hopefully cost reduced and volume discounted at 1000 MOQ. :D
Quick update, just to let everyone waiting know I am working on this now that Teensyduino 1.53 is released. It's my top priority. I hope to have chips available for you in a couple weeks.
Sorry for the naive question.... It sounds like Paul sells chips already programmed. With that, is the boot loader chip available from a place like DigiKey? Or do you order them from Paul and send to a pcb manufacturer/assembler?
Sorry for the naive question.... It sounds like Paul sells chips already programmed. With that, is the boot loader chip available from a place like DigiKey? Or do you order them from Paul and send to a pcb manufacturer/assembler?

you order them from Paul
Can we order them from paul now, despite not showing up on the current bootloaders webpage, if not when can we expect them for sell?