diff --git a/repositories.txt b/repositories.txt
index a5b6d890..e65664ca 100644
--- a/repositories.txt
+++ b/repositories.txt
@@ -4600,3 +4600,4 @@ https://github.com/Seeed-Studio/Seeed_Arduino_24GHz_Radar_Sensor
 https://github.com/danyev3/JAREL
 https://github.com/vChavezB/NoBlockEEPROM
 https://github.com/Seeed-Studio/Seeed_Arduino_8Channel_I2C_Hub
+https://github.com/PR-DC/PRDC_RS485HD_STM32