diff --git a/firmwareapi/pycom/machine/pin.md b/firmwareapi/pycom/machine/pin.md
index 04bec46..b1dd63e 100644
--- a/firmwareapi/pycom/machine/pin.md
+++ b/firmwareapi/pycom/machine/pin.md
@@ -44,6 +44,8 @@ Initialise the pin:
   * `None` - no pull up or down resistor.
   * `Pin.PULL_UP` - pull up resistor enabled.
   * `Pin.PULL_DOWN` - pull down resistor enabled.
+* `*`
+  * Pin value: `0` or `1`
 * `alt` is the id of the alternate function.
 
 Returns: `None`.