diff --git a/testhal/STM32F4xx/UART/readme.txt b/testhal/STM32F4xx/UART/readme.txt
index bd9cbf6e5..19a8e26da 100644
--- a/testhal/STM32F4xx/UART/readme.txt
+++ b/testhal/STM32F4xx/UART/readme.txt
@@ -12,7 +12,7 @@ The application demonstrates the use of the STM32F4xx UART driver.
 
 ** Board Setup **
 
-- Connect an RS232 transceiver to pins PA2(TX) and PA10(9).
+- Connect an RS232 transceiver to pins PA2(TX) and PA3(RX).
 - Connect a terminal emulator to the transceiver (38400-N-8-1).
 
 ** Build Procedure **