diff --git a/README.md b/README.md
index 169d810..d1b5be5 100644
--- a/README.md
+++ b/README.md
@@ -129,10 +129,10 @@
 * Copy the `devtimer.py` and `tm1637.py` files onto your
   Pi Zero.  You can then start the timer with `./devtimer.py`.
 
-* By default, the code currently writes a lot of debug info to
-  the Pi's tty so you can watch all manner of things fly by.
-  If it bugs you, just change `DEBUG` to `False` at the top of the
-  code.
+* The DEBUG variable turns debug output to the console on- and off.
+  It's for use by the developer and should be left set to `False`.
+  Enabling this significanly interferes with the timer's accuracy at
+  least on small footprint machines like the Pi Zero.
 
 
 ## Operating The Timer
@@ -200,7 +200,7 @@
 here are a few ideas on how it can be tuned or adjusted:
 
 * VERY IMPORTANT: Do **NOT** run the timer with `DEBUG = True`. This
-  option is for the sofware developer only and introduces extra
+  option is for the software developer only and introduces extra
   output that *makes the timer less accurate*.  So, unless you are
   hacking on the hardware or software, leave this set to `False`.