diff --git a/Retron-77.md b/Retron-77.md
index 4c2789d..4a243e3 100644
--- a/Retron-77.md
+++ b/Retron-77.md
@@ -31,7 +31,7 @@ There is no onboard flash memory.
 
 ## UART
 
-There is a single UART header on the mainboard that can be used to obtain a serial console to both the U-Boot bootloader and the linux system running on the device. The UART is configured by both U-Boot and linux at 115200 bps.
+There is a single UART header (labelled as UART0) on the mainboard that can be used to obtain a serial console to both the U-Boot bootloader and the linux system running on the device. The UART is configured by both U-Boot and linux at 115200 bps.
 
 [[https://github.com/stella-emu/stella-emu.github.io/blob/master/r77/uart.jpg]]