Hello,
I'm looking for a sanity check and advice for communicating with the ROM bootloader on the MIMXRT1020-EVK via UART. I'm planning on using an RT1020 in a project, and before I do, I want to make sure I have the hardware interfacing understood.
My setup for interfacing with the ROM bootloader:
- SW8/boot config set to 0b0001 (0b01 boot config for Serial Downloader)
- All JTAG jumpers (J44-J50) removed
- UART interface connected TX to GPIO_AD_B0_07 and RX to GPIO_AD_B0_06
- Tried powering from J2, J9, and J23 separately
So far, I've been trying to use blhost to get a ping response. I've tried power cycling and connecting with and without UART connected then running blhost -p /dev/tty.usbserial-FT99ICPP,115200 -- get-property 1 but every time I get the response "No response received for ping command". Looking at my logic analyzer, I see no signal changing on my RX line.
In addition to this, I've successfully loaded the Flashloader project and been able to interface with that. I've also ported, built, and flashed the second bootloader from the AN12604 app note. So I feel confident I have the UART interface working, since they should all use the same LPUART1 configuration.
What might I be missing that could explain why I'm unable to interface with the ROM bootloader? I've seen mfgtools mentioned, but I can't seem to get it to recognize my dev board in my windows VM (SE Blank RT Family does show up as a connected device in the VM, but doesn't list with uuu.exe -lsusb). I've also seen sdphost mentioned, but I was unsure if it works with the RT1020 since it's not listed here (https://mcuxpresso.nxp.com/mcuxsdk/latest/html/middleware/mcu_bootloader/docs/iMXRT1020_Flashloader_...). I've also been operating under the assumption the ROM bootloader responds to SDP the same way flashloader and second bootloader do, and maybe that's my mistake?
Thank you for your updated information.
If you meet any issue in the future, welcome to create the new question post.
Thank for you, @mayliu1 , I did not realize ROM bootloader communication was completely different from communicating with the flashloader or second bootloader. I was able to communicate with the ROM bootloader using sdphost.
Hi @rob-RL ,
Thank you so much for your interest in our products and for using our community.
First, I think your Setup Looks mostly correct, you set RT1020 chip Boot Mode as serial downloader mode, and also UART interface is correct.
Second, I suggest you use Sdphost instead of blhost.
1: blhost is used after the ROM bootloader has responded and is ready to accept commands.
2: sdphost is used to initiate communication with the ROM bootloader using the Serial Download Protocol (SDP).
Wish it helps you.
If you still have question about it, please kindly let me know.
Best Regards
MayLiu