Custom teensy 3.6 not work

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Armadafg

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Hi everybody,

I created my custom teensy 3.6 card with a four layer PCB.

I solder the essential for the power supply, the USB and the MKL02 that I have desolders of an original teensy 3.6 await the delivery MKL02 sold directly by PJRC that I buy. But delivery to France will put at least 2 weeks

I have the signal on the USB port 0 but nothing happens when I connect to the pc and I press the button reset or reprogramming.

I suspect the Load Capacitance of this crystals but I do not know how to rectify.

https://lcsc.com/product-detail/SMD-Crystals_Yangxing-Tech-YST310S32-768KHz12-5pF10ppm_C94279.html
https://lcsc.com/product-detail/49S_Hosonic-Elec-E49A16E00000KE10CO_C114981.html

The "MNI" will not be the cause of the problem and the welding is good quality but we never know.
The vbat is powered by 3.3V.
I tried Swapping the D + and D- signals on the USB connector.

I buy the MK66 here and I tested 2.
https://www.mouser.fr/ProductDetail/841-MK66FX1M0VMD18

thank you in advance for your help :)
 
Here are the parts of the circuit that pose problem. This is my first PCB custom so it's not very nice to see but it will function. And don't laugh ;)
I tried every combination with the reset and reprog button

The reset of the PCB filled with other function and the part USB hub function has 100%. And the detention and well 5V and 3.3V. I have not yet check it at the oscilloscope.

Capture.PNG
Capture2.PNG
Capture3.PNG
 
PS yes I noticed errors including the level of the retention of the usb 1 but nothing vital to the proper functioning of the MK66
 
Looks like VREG_OUT is unconnected on your schematic.

Pretty sure the USB can't work this way, even if you apply 3.3V to all the other VDD pins. The USB transceiver inside the chip gets its power from VREG_OUT. You need 3.3V power on that pin.
 
Hoooo sh***

In addition I had seen on the page of the store as it was necessary to connect this pin. I forgot it. Thank you Paul.

I will try to connect it with some stuff.

As we say here "j'ai le seum".

Anyway thank you for your help. I hope the problem comes from there.
 
FE1.1S DP1 (11) connected to MK66 USB0_DM (H2)
FE1.1S DM1 (10) connected to MK66 USB0_DP (H1)

doesn't look right
 
yes but I already try to cross the cables but it did not change anything.

I will recommend a PCB with the correction on the voltage of the USB1, connect the DP pin on the DP and DM on DM. and connect the VREG_OUT.

I have already made the changes but before that I would like to have your opinion about the crystals.

And if you have any other suggestion do not hesitate :) . I would like to order it quickly.
 
Hi everybody,

I corrected the problem on my circuit board, that said my pc detect well something on the USB port but it is not the teensy.
I don't know what it is and I don't know how to solve it.
I try with all the combination with the reset button and reprogramming but nothing is done. The USB device is no longer visible when I press the reset button.
I don't know if the reflow is good and if the MKL04 works well (The MKL04 comes directly from the teensy shop)

Capture.PNG
PCB V410 cpu2 schemas.PNG
PCB V410 cpu2.PNG

Thank you in advance for your help
 
Next step is to measure the voltage on the Program and Reset signals. Both are supposed to be 3.3V normally. When you press the button, it's supposed to short Program to 0 volts. The MKL02 chip is supposed to respond by pulling Reset low while Program remains low. So check that both really are going low while you hold the button pressed.
 
Thank you very much for your help.

The voltage goes well to 0 or 3.3volt in function of the position of my buttons

I will check but it seems to me that this is actually what I had to observe, the reset does not pass low when the program goes low.
And if it is the MKL02 that does not respond that would mean that the MK66 works well but not the MKL02 is that it?
 
3.3V on the Program pin is good. That means the MKL02 chip was able to boot up and turned on its internal pullup resistor on that pin.

Maybe some of the other signals aren't connected properly?
 
Hi,
At this time i have the case where the program pin is at 0volt. I was able to send a program once but after nothing.
I tested all possible combinations with the button programe and reset but nothing happens. Is it possible that a fault on the MK66 blocks the proper functioning of the MKL02?
 
Neither chip should cause the Program signal to be low. Program isn't even connected to the K66 chip at all.

Only the pushbutton makes Program low.

Maybe your board has been damaged somehow, like a piece of metal or debris causing that signal to short to GND?
 
ok, I deepened my diagnosis.

I did tests with 2 different MLK02 and tested the conections.

The pin rest and Program it is well to connect to the MKL02 and it does not short to GND.
When I feed the chips in 3.3volts the program pin while floating and the reset pin is at LOW (0 volt).

I already tried to put a resistance pull up on the Rest pin and Program but the result is the same
 
IT's WORKS!!!! :cool:

I do not know why but by doing the measurements with my old oscilloscope on the MLK02 the MK66 is awake and all to work normally.
Sometimes I had to start again for it to work again but now for a one week I do not need any more.

I'm still not sure why but it works but it works :)
 
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