From 5a249d7dc09c36d3953a6e31687198ed6ee266bc Mon Sep 17 00:00:00 2001
From: cuu <gnubsd@me.com>
Date: Thu, 6 Jun 2024 06:17:03 -0700
Subject: [PATCH] update readme of devterm_fan_daemon_cm4

---
 Code/devterm_fan_daemon_cm4/README.md | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/Code/devterm_fan_daemon_cm4/README.md b/Code/devterm_fan_daemon_cm4/README.md
index d6d18cd..ba6c746 100644
--- a/Code/devterm_fan_daemon_cm4/README.md
+++ b/Code/devterm_fan_daemon_cm4/README.md
@@ -23,4 +23,15 @@ then restart systemd service to take effect
 
 `sudo systemctl restart devterm-fan-temp-daemon`
 
+## How to control the fan from GPIO
+
+``` start the fan
+sudo gpio mode 17 out
+sudo gpio write 17 1
+```
+
+```stop the fan
+sudo gpio mode 17 out
+sudo gpio write 17 0
+```