Custom board blink 10 times using PJRC pre-programmed MKL02

C

cicamrgoba

Member
Hello
I' m using PJRC pre-programmed MKL02 on custom iMXRT1062 board. The board complete the powerup Sequence, but the board blink the LED 10 times, there is a way to disable Ethernet MAC verification? Can you share with me the bootloader Sequence to know which peripherals are wirking (spi port, Ethernet port, internal clock)
Best regards

Carlos
 
10 Blinks = Serial Number Already Assigned A problem occurred with the serial number & ethernet mac address assignment.

Is the Flash new or from a prior functional Teensy? And the Bootloader chip? Fresh from PJRC and unused?
 
Hello, thanks for your answer.
We have 4 boards, all with new flash chips, in one we get 10 blinks, 3 boards the led blink one time.

Carlos
 
All boards are identicals, I'm reading that one blink with 50% duty cycle means USB problems.
I use new chips from pjrc flash and mkl02

Best regards

Carlos
 
Hello
My board complete the power up sequence sucessfully, Detect flash memory ID, but I don't know the point when fail. One board present Serial Number Already Assigned. And 3 Slow Steady 1 Second 50% On/Off = No USB Communication.

With thia information I want to know if the jtag communication is good, and if the clock is stable, but I don't know the bootloader sequence related to blink leds


Carlos
 
This is my board I want to use 2 Ethernet ports, the bootloader chip is connected to J12
 

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Yes, I understand the POWER UP sequence, my board complete the full sequence, but I need the botloader sequence: i.e.
1. Load first step loader in internal ram
2. Configure clocks, gpios,peripherals
...
3... Read ID flash memory if not supported then blink 3 tiimes
4...
The blinks occurrs not in the power up sequence, I need to know the poiint of failure in the boot sequence.
 
The MKL02 is not a "bootloader". It is involved in the power-up sequence and takes control of the CPU when requested, but it does not take part in the boot process. The steps you're talking about (configuring clocks, peripherals etc.) are done by the IMXRT internal ROM and the startup code of the program in the flash memory.
 
Thanks for your answer, MKL02 blink the LED, so MKL02 is running some code to check the correct functionallity. Im my case 10 blinks and one blink, Can I asume that MKL02 save startup code to flash and iMXRT is running it?
 
No, it means the MKL02 has already been used to initialize an IMXRT chip but it does not match the one currently connected.
 
Ok, so the best way is use jtag port to load a different loader ? I'm using flash and MKL02 fron pjrc. So my board don't work with this configuration

Best regards
 
Last edited:
Let's focus on your boards which have the 3 blink error. Normally 3 blink means the flash chip is not soldered or an incompatible part.

I see this empty place on your photo. Is this where the flash chip should be?

1775513560287.png
 
Hello
This is an old picture, I've already mount a PJRC flash. The current problem are with 10 blinks and 1 blink.

Best Regards
Carlos
 
Let's focus on the "1 blink". I'm guessing that is the slow steady blink which indicates no USB communication while in bootloader mode?

If so, maybe we can help you if you show the PCB layout and/or schematic. This problem is almost always an issue with the USB wires. If you show us the design, maybe we can see a problem you've missed? But we can't notice any problems in the wiring unless we have the laying pictures or schematic.

The 10 blink problem is due to using the bootloader chip with a differing RT1062 chip. Solve this by using the bootloader chip with the same RT1062 chip it originally initialized.
 
Hello Thanks for your answer
I'm attaching schematics, basically is the same teensy schematic but with separated MKL02 circuit
 

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Since we know the blink means USB problem, first part of the schematic I viewed was this:

1775530122696.png



I don't understand this part for J6. It has only 7 pins.

The USB connector in your photo appears to have 12 pins.

1775530226583.png
 
2 other minor possible issues.

GPIO_AD_B0_05 (BOOT_MODE_1) is supposed to connect to GND. But it is wired to JP1, uncertain how JP1 actually connects.

GPIO_SD_B1_05 is supposed to be left unconnected.

1775530498124.png
 
Hello, kicad symbol can hide signals with the same name and different number and show only one, so D+ is a group for 2 signals, I've already use This symbol/footprint before.


Boot_mode_1 is connected to gnd.
GPIO_SD_B1_05 is unconnected, just have a wire with unused label
 
Something must be connected wrong, or not connected, because you are getting the blink which indicates no USB communication.

I viewed the PDF file you provided. Those are the possible problems I was able to see. I tried to do as much as I could with the only info I have.

Yes, you have said these things are not problem. But something is definitely wrong. If it were 100% correct, you would have the same communication as Teensy 4.1.
 
One more possible problem, U8 has wrong part number. This would explain a 3 blink error. But it does not explain the slow blink for no USB.

1775537878549.png
 
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