The ON/OFF button is connected to i.MX 8M Plus ONOFF pin. In the ON state, if ON/OFF button is held longer than the debounce
time, the power-off interrupt is generated. If the button is held longer than defined max timeout, the state will transit from ON to
OFF, and send PMIC_ON_REQ signal to turn off the powers of PMIC. In the OFF state, if the ON/OFF button is held longer than
the OFF-to-ON time, the state will transit from OFF to ON, and send PMIC_ON_REQ signal to turn on the powers of PMIC.
2.22.2 Reset button (SW2)
The RESET button (SW2) is directly connected to the PMIC PCA9450C. Holding the RESET button will force a reset of the PMIC
power outputs except NVCC_SNVS_1V8 on the EVK board. The i.MX 8M Plus applications processor will be immediately turned
off and reinitiate a boot cycle from the OFF state.
2.23 User interface LED indicators
There are four LED indicators on the board. These LEDs have the following functions:
• Main Power Supply (D25)
— Red – The board is powered on.
— OFF – The board is powered off.
• System Status (D1) on 8MPLUSLPD4-CPU
— Green Blinking – CPU is running well.
— OFF – CPU is not running.
• A53 UART (D16/D17)
— D17 Green light flashing – The UART data transmitted to PC.
— D16 Orange light flashing – The UART data received from PC.
• M7 UART (D20/D21)
— D21 Green light flashing – The UART data transmitted to PC.
— D20 Orange light flashing – The UART data received from PC.
NXP Semiconductors
Specifications
i.MX 8M Plus LPDDR4 EVK Board Hardware User's Guide, Rev. 0, March 9, 2021
User's Guide
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