Integrate Teensy 4.1 design on custom PCB

Maybe something you removed really was needed?

Or perhaps your design is perfect, but the soldering or other physical construction has a problem?

Please understand we can't see your hardware or schematic, and we have almost no information other than a screenshot of an error you would get if nothing was connected you PC. The best anyone can do is blind guesswork. But there isn't even much info to try guessing.

Hello Paul,

Yeah, I think I asked questions so vaguely... I attached the schematic we are using for everyone's reference.
If you see something, please let me know.

I appreciate you all for being so responsive! MCU.jpg
 
Schematic looks like it should work.

First check is whether everything powered up. Refer to "Power Up Sequence" on the T4 bootloader chip page:

https://www.pjrc.com/store/ic_mkl02_t4.html

Just use a voltmeter and check locations mentioned in all 8 power up steps.

Hello Paul,

Thanks for your reply! I followed the steps and was able to found that there was no supply at node 8, I cross-checked with my Teensy and saw that the caps should be connected to VIN which was originally missing on the schematics. I will do workaround with it and then will update you on the progress or if I have more questions. :)
 
Schematic looks like it should work.

First check is whether everything powered up. Refer to "Power Up Sequence" on the T4 bootloader chip page:

https://www.pjrc.com/store/ic_mkl02_t4.html

Just use a voltmeter and check locations mentioned in all 8 power up steps.

Hello Paul,

Please disregard my statement that port 8 should be connected to VIN. I just rechedked the teensy and it isn't. However, I can't still seem to push through to the programming mode in teensyduino as the device is still not recognized even though the voltages are all okay... MKL02 have 3.3 stable input voltage however, I am not getting any voltage from VDD_SOC

Appreciate if you can advice how to proceed with this instance... Thanks again!
 
Check the voltage on the Program signal (the pushbutton when not pressed). It should be 3.3V if the MKL02 started up and enabled the pullup resistor.
 
Can you check if it really has 3.3V power at pin 1 (VDD)?

If powered, definitely not a good sign. Check the PJRC order, as mistakenly ordering the chip meant to implement Teensy 3.x would cause this result. So would a blank chip (if you used a contract manufacturer and they didn't buy the chip from PJRC... yes it's come up a few times).
 
Can you check if it really has 3.3V power at pin 1 (VDD)?

If powered, definitely not a good sign. Check the PJRC order, as mistakenly ordering the chip meant to implement Teensy 3.x would cause this result. So would a blank chip (if you used a contract manufacturer and they didn't buy the chip from PJRC... yes it's come up a few times).

Hello Paul,

As mentioned, I'm using the blank chip... I was not aware of this part prior doing the design.
I'll place an order for this chip and once replaced, I'll make sure to send an update here in the forum.

Have a good day! :)
 
Can you check if it really has 3.3V power at pin 1 (VDD)?

If powered, definitely not a good sign. Check the PJRC order, as mistakenly ordering the chip meant to implement Teensy 3.x would cause this result. So would a blank chip (if you used a contract manufacturer and they didn't buy the chip from PJRC... yes it's come up a few times).

Hello Paul,

Good day! the bootloader chip s now replaced and I've run over the voltage checks and all is okay now. Now I'm trying to upload the code and I am only seeing the attached photos.
To give you more detail, when I push the prog button I get two blinks and then nothing.

Looking forward to your suggestions on this! Have a great day!

Kind regards,
Hannah

Teensy4-1(2).jpgTeensy4-1(1).jpg
 
On a brand new custom PCB, for the first upload you will need to press the pushbutton (or otherwise cause the Program signal to go low as if the pushbutton was pressed) to cause the bootloader chip to take control of the RT1062 chip and run the bootloader.

Automatic upload from Arduino IDE only works if Teensy is running a previous program which listens for the USB message that requests going into programming mode. Every Teensy has the Program pushbutton, so you have a way to recover if you ever load a program which doesn't listen on the USB port (disable interrupts, sleep the CPU, turn off the USB peripheral, crash in some unexpected way, etc). Every Teensy is tested at PJRC where the final test loads the LED blink example, so automatic upload works "out of the box" on Teensy because is was programmed at PJRC. Obviously on a brand new PCB you've just built, it won't have any previous program to listen for the USB message that asks for automatic upload. So you have the press the pushbutton.
 
Hello Paul,

This is noted. I still can't go to the HalfKay mode even after pushing the prog button. Whenever I try to into the HalfKay mode, the MIMXRT1062DVJ6B is showing up then just go nothing.
I don't know if this has something to do with it, but I am using MIMXRT1062CVL5B instead of the orginal chip. Would this be an issue?
Also, is there any pin I can check to see if I enter the programming mode successfully other than the GUI?

Thanks for your help on this!
 
Is the red LED blinking? On your original schematic, I believe it was D4.

When things go wrong, that LED is supposed to blink 2 to 13 times to indication what's wrong. The meaning of each is documented on the bootloader chip page. Scroll down to "Troubleshooting & Diagnostic Blink Codes".
 
Hello Stefan,

Thanks for your reply! I checked the documentation yesterday and saw the three blinks so we already debugged it.
Today, we just tested and the integrated Teensy is working perfectly fine! Just still need to check it's performance in the long run :)
But functionality wise, we are happy with the result! Thank you very much for answering my questions!

Have a nice day! :)
 
hello, i have similar 3 blinks of the LED after pushing the button, and this
1704786455529.png
and then disappearing.
Would your share how did you solve it. I can't see any problem with the MKL or W25Q64 connection to the MIMX

Thanks, Alex
 
hello, i have similar 3 blinks of the LED after pushing the button, and this
View attachment 32843 and then disappearing.
Would your share how did you solve it. I can't see any problem with the MKL or W25Q64 connection to the MIMX

Thanks, Alex
Hello Alex,

The issues we encountered are:
-Incorrect MKL - used the unflashed component thus incorrect measurement of voltage of DCDC_PSWITCH
Steps for debugging:
1. Followed the power up sequence: https://www.pjrc.com/store/ic_mkl02_t4.html
2. Measured each voltage levels and compare to the target level
3. Replaced the MKL to the one from PRJC Store
This solved the issue-all the voltage levels met the target values

-3 blinks - Flash chip error
Steps for debugging:
1. Reviewed the schematic used on the board versus the developers schematic, found that there have been swaps on the connection between W25Q64 and MIMX
2. Reworked the PCB to correct the connection using flying wire
3. Followed power up sequence; measure each voltage level and compared it to the target level
4. Opened Arduino - selected teensy
This solved the issue - no blinking and was able to upload the code. You might also need to check the connection of your switch.
We removed ours and just manually short the pins through wire.

Hopefully this can help. Otherwise, you can probably ask Paul for more suggestion. He's been a great help for our case.

Best regards,
Hannah
 

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Hello Hannah,
Thank you for response!
We bought MKL from PJRC and the connection looks fine, the only difference is the package of w25q64
The voltage levels also looks ok.
I attached the snapshot of the connection, may be you can see something...
Thanks, Alex
1704791162854.png
 
Hi Hannah,
1704793328270.png

Thanks a lot,
pin8 of w25 is connected to Vdd and are you sure it is going directly to pin11 of MKL? it's for LED only
but now i see that the EXP PAD (pin9) of W25 is connected to GND, (this should be ok)
1704793883687.png

Am I correct or missing something?
Regards
Alex
 
I see your schematic says "W25Q64/128MBIT". That doesn't make much sense to me, as W25Q64 is 64 Mbit (8 Mbyte).

Can you give the full part number of the flash memory used? Or show a clear close-up photo of the actual chip used? Using an incompatible flash memory chip would give the 3 blink error.
 
At least the good news is the 3 blink error shows your PCB design is probably ok. Odds are good it should work when you solder the correct flash chip.
 
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