diff --git a/Retron-77.md b/Retron-77.md
index d3c56a0..02eb00e 100644
--- a/Retron-77.md
+++ b/Retron-77.md
@@ -11,7 +11,7 @@ The R77 contains the following hardware
  * A Weltrend WT51F104S MCUs that drives the cartridge dumper (connected via UART)
  * Another WT51F104S that drives the front panel with the joystick ports (connected via I2C)
  * SD card slot
- * Micro USB connector (for power only)
+ * Micro USB connector
 
 There is no onboard flash memory.
 
@@ -35,6 +35,14 @@ There is a single UART header (labelled as UART0) on the mainboard that can be u
 
 [[https://github.com/stella-emu/stella-emu.github.io/blob/master/r77/uart.jpg]]
 
+## USB
+
+The external micro USB connector has its data lines connected and can be used to connect USB peripherals (in conjunction with an USB OTG adaptor to power the device). In addition, there is an additional USB port exposed on the board as JP1:
+
+[[https://github.com/stella-emu/stella-emu.github.io/blob/master/r77/uart.jpg]]
+
+Credit for discovering this (both header and micro USB) goes to Fluxit on AtariAge.
+
 # Software
 
 ## Overview