How to access bootloader on Apalis iMX6?

The end goal is to be able to use Boot2Qt on a Toradex Apalis iMX6. I’m using an Ixora carrier board.

I’m following this guide on Qt’s website: http://doc.qt.io/QtForDeviceCreation/qtee-preparing-hardware-apalis-imx6.html

I need to be able to access the bootloader environment to make the device boot from SD card. I get stuck at this stage:

“Connect a serial cable to the device and enter into the U-Boot environment by pressing any key before the autoboot.”

I’m getting into a bit of bother when trying to boot into the bootloader environment. I have connected a 2x5 header to UART1, which is in turned connected to a null modem serial cable, connected to a serial to USB convert to my laptop (Windows 10).

I’m using TeraTerm to connect to the COM port on my laptop - over which I hope to be able to interrupt the start procedure with a key press to access the bootloader. I am using the correct settings for the serial connection (115200 baud rate, 8 bit data, no parity, 1 stop bit).

However - I just get a blank terminal, and no response from the device. The device appears to boot as normal into the pre-installed operating system.

Can anyone think of any reasons why this may not be working? There may be something quite fundamental I’m doing wrong. All other questions and answers seem to get into this bootloader without issue - here’s hoping it’s me just missing something basic!

Hope this is enough information - happy to give more if required.

Cheers
Andy

May be you find this article helpful.

Thanks sanchayan,

Unfortunately no luck with this. I had a fully connected serial cable with RX and TX crossed over - I have since cut the RTS and CTS lines, according to the link you provided, to stop the hand shaking. I still see no output at my console.

Please note that just cutting the RTS and CTS lines won’t necessarily help any and is quite ignorant concerning the basic UART concepts as e.g. outlined here.

The end goal is to be able to use Boot2Qt on a Toradex Apalis iMX6. I’m using an Ixora carrier board.

I’m following this guide on Qt’s website: http://doc.qt.io/QtForDeviceCreation/qtee-preparing-hardware-apalis-imx6.html

You may also make an enquiry about this to whoever wrote that guide asking them for support.

I need to be able to access the bootloader environment to make the device boot from SD card. I get stuck at this stage:

“Connect a serial cable to the device and enter into the U-Boot environment by pressing any key before the autoboot.”

I’m getting into a bit of bother when trying to boot into the bootloader environment. I have connected a 2x5 header to UART1, which is in turned connected to a null modem serial cable, connected to a serial to USB convert to my laptop (Windows 10).

Which part of this chain are already proven working? E.g. have you tested your serial to USB converter, your null modem serial cable, your 2x5 serial header, Ixora carrier board and/or Apalis iMX6 module? BTW: What USB to serial converter are you using?

I’m using TeraTerm to connect to the COM port on my laptop - over which I hope to be able to interrupt the start procedure with a key press to access the bootloader. I am using the correct settings for the serial connection (115200 baud rate, 8 bit data, no parity, 1 stop bit).

How exactly did you asses that your settings thereof are correct?

However - I just get a blank terminal, and no response from the device. The device appears to boot as normal into the pre-installed operating system.

And what exactly is this pre-installed operating system?

Can anyone think of any reasons why this may not be working?

Anything could be wrong really. The most important thing in Engineering is to go step by step validating each step before the next one is attempted:

There may be something quite fundamental I’m doing wrong. All other questions and answers seem to get into this bootloader without issue - here’s hoping it’s me just missing something basic!

Hello, same problem as OP here. I think I can answer some of the questions you are asking.

How exactly did you asses that your settings thereof are correct?

I guess the op took it from the “apalis tegra” example here:

Because if you check in its proper place (like my case for people with ixora and apalis imx6),
the uart configuration should be appear here:

But its not.

Apart from that, in theory its necessary to put the unit in recovery mode. The only solution recommended in the APALIS imx6 datasheet is to short pads but if you check in this forum, you can do this:

" To enter recovery mode you can use the HW method described in the instructions or enter the bootloader console by connecting a serial console to UARTA and pressing space during the first 2 seconds of boot. Then type: bootfrom usb reboot and the module will enter recovery mode without needing HW operations. "

Found here:

Which by the way, doesnt appear in any other datasheet or wiki from toradex. And I dont know what is UARTA but lets guess is UART1. Anyway this doesnt work neither.

The most important thing in Engineering is to go step by step validating each step before the next one is attempted:>

Dificult to validate if you have incomplete information from the supplier…

So based on this, is it possible to know how I can get in the bootloader on an Apalis imx6 plugged into ixora 1.1 not shorting the pads?. I have a heatsink with thermal paste and it would be convenient to find an alternative way.

Which configuration should I use for the serial connection?. Which connector on Ixora 1.1 should I use? I am using putty but I could use teraterm (im on windows) if recommended.

Hi @juantex

Would the command bmode usb in u-boot on UART1 (X22) work for you? You are free to use teraterm or putty.

Regards,
Stefan

Thanks for your answer stefan_e, I will check and confirm you if works.

Just double checking:
115200 baud rate, 8 bit data, no parity, 1 stop bit Right?

Should I disable the hardware flow control? (rts,cts lines)

Exactly 115200 baud, 8 bit data, no parity, 1 stop bit and hardware flow control should be disabled.

Perfect, thanks!