docs: add CONTRIBUTING.md

libdriver · libdriver · commit 2195371a79ff · 2022-12-10T14:10:31.000+08:00
diff --git a/project/stm32f407/README.md b/project/stm32f407/README.md
@@ -4,7 +4,7 @@
 
 Chip Name: STM32F407ZGT6.
 
-Extern Oscillator : 8MHz.
+Extern Oscillator: 8MHz.
 
 UART Pin: TX/RX PA9/PA10.
 
