Hardware requirements
- Micro USB cable 
- MIMX8MM6-EVK board 
- J-Link Debug Probe 
- SD card with uboot 
- 12V power supply 
- Personal Computer 
Board settings
No special settings are required.
Prepare the Demo
- Prepare an SD card with the prebuilt U-Boot image. Then, insert the SD card to the target board. 
- Connect a USB cable between the host PC and the J901 USB port on the target board. 
- Connect 12V power supply and J-Link Debug Probe to the board, switch SW101 to power on the board 
- Open a serial terminal with the following settings: - 115200 baud rate 
- 8 data bits 
- No parity 
- One stop bit 
- No flow control 
 
- Download the program to the target board. 
- Launch the debugger in your IDE to begin running the demo. 
Running the demo
Follow the output log, lock and unlock the sema4 gate in uboot. The whole log:
SEMA4 uboot example start
Lock sema4 gate in uboot using:
 > mw.b 0x30ac0000 1 1
Unlock sema4 gate in uboot using:
 > mw.b 0x30ac0000 0 1
SEMA4 uboot example success