# GPIOD User Guide

This document lists the common gpiod commands for Quectel Pi M1/L1. The checked board uses libgpiod v1.6.3, so this page uses v1 syntax.

## Install and Check

```bash
sudo apt update
sudo apt install -y gpiod
gpiodetect --version
gpiodetect
gpioinfo
```

| **Command** | **Purpose** |
| --- | --- |
| `gpiodetect` | View GPIO controllers |
| `gpioinfo` | View GPIO line status and usage/ownership |
| `gpioget` | Read input state |
| `gpioset` | Set output state |
| `gpiomon` | Monitor edge events |

## Controller Example

```
gpiochip0 [400000.pinctrl] (114 lines)
gpiochip1 [1c40000.qcom,spmi:qcom,pm6125@0] (9 lines)
gpiochip2 [soc:spf_core_platform:lpi_pinct] (19 lines)
```

## Common Commands

```bash
# Show main controller lines
gpioinfo /dev/gpiochip0

# Read line 36 on gpiochip0
gpioget gpiochip0 36

# Drive high for 5 seconds
gpioset --mode=time --sec=5 gpiochip0 36=1

# Monitor rising edge events
gpiomon --rising-edge gpiochip0 36
```

## Version Difference

| **Function** | **Current M1 v1 Syntax** | **Syntax That May Appear in Newer Materials** |
| --- | --- | --- |
| Read | `gpioget gpiochip0 36` | `gpioget -c gpiochip0 36` |
| Output hold | `gpioset --mode=time --sec=5 gpiochip0 36=1` | `gpioset -c gpiochip0 -p 5s 36=1` |
| Rising-edge monitoring | `gpiomon --rising-edge gpiochip0 36` | `gpiomon -c gpiochip0 -e rising 36` |

## Notes

- GPIO line offset is not the physical header pin number.

- Do not control lines marked with `[used]` or an existing consumer.

- After `gpioset` exits, output state may return to default; do not rely on residual level.