add Rob's changes

inductors_motors/index.html

@@ -47,5 +47,5 @@
 
 </xmp>
 
-<script src="../strapdown-gh-pages/strapdown-gh-pages/v/0.2/strapdown.js"></script>
+<script src="../../../../strapdown/strapdown.js"></script>
 </html>

microcontroller/index.html

@@ -31,17 +31,25 @@ Pins:  Supply (2.7-5.5V), ground, reset.  Other pins available for input and out
   This is used, for example, to make a simple button input circuit.
 
   ![picture](../images/input_pullup.jpg)
+
+  ---
+
   - Analog to Digital converter.  (ADC)  "Analog" input.  Uses digital process to infer analog voltage.
+
+![picture](../images/pot_input.jpg)
+
+---
+
   - Built-in analog amplifier.  Attiny45 has a 20X differential amplifier.
 
 #### Output.
-- Digital output.  Low, high, tri-state.
+- Digital output.  Low (0 V), high (Supply voltage, e.g. 5V), tri-state (floating, with high input impedance).
 - what can the ucontroller drive?
   - Things with high input impedance: FETs, Piezoelectric transducers, other microcontroller inputs.
   - To some extent, things with low imput impedance:  maximum current is 40mA per I/O pin.  Enough to (over)drive LEDs.
   - One way to get "Analog" out:  Pulse width modulation (PWM)
 
-
+![picture](../images/input_output.jpg)
 
 ---
 
@@ -49,5 +57,5 @@ Pins:  Supply (2.7-5.5V), ground, reset.  Other pins available for input and out
 
 </xmp>
 
-<script src="../strapdown-gh-pages/strapdown-gh-pages/v/0.2/strapdown.js"></script>
+<script src="../../../../strapdown/strapdown.js"></script>
 </html>