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products:sbc:common:applications:gpio:uart
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Table of Contents
UART
Introduction
This document mainly introduces the usage of UART on 40-Pin Header.
UART Information
| PWM | PIN | GPIO(#Number) | DT Overlays Node | Device Node | |
|---|---|---|---|---|---|
| VIM1 | PWM_AO_A | 35 | GPIOAO_3 (#504) | pwm_ao_a | /sys/class/pwm/pwmchip4 |
| VIM2 | PWM_D | 35 | GPIODV_28 (#478) | pwm_d | /sys/class/pwm/pwmchip1 |
| VIM3/3L | PWM_F | 35 | GPIOX_7 (#432) | pwm_f | /sys/class/pwm/pwmchip4 |
| VIM4 | PWM_F | 35 | GPIOY_8 (#482) | pwm_f | /sys/class/pwm/pwmchip4 |
Enable UART
Uart PIN in 40-Pin Header is PIN15 and PIN16. Refer to Device Tree Overlay.
Enable uart node via device tree overlays. Edit /boot/env.txt to add uartX to overlays. E.g.
overlays=uart4 pwm_ao_a pwm_f i2c0
Reboot to effect.
- VIM1/VIM2/VIM4 - uar4
- VIM3/VIM3L - uart3
Check UART Node
After reboot, you will see the uart device node.
- VIM1/VIM2/VIM4 - /dev/ttyS4
- VIM3/VIM3L - /dev/ttyS3
Last modified: 2022/07/12 22:51 by nick