edison.md: Add warning for gpio 4 on miniboard

Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>

diff --git a/docs/edison.md b/docs/edison.md
index 7e15df8..b493905 100644 (file)
--- a/docs/edison.md
+++ b/docs/edison.md
@@ -42,6 +42,7 @@ Intel(R) breakout board
 
 - Both I2C buses are available 1 & 6
 - IO on the miniboard is 1.8V
+- Requesting GPIO 4 will break your FTDI UART console, so bear in mind when trying to use it
 
 Please see the following table on how the physical pins map to mraa pin numbers