diff --git a/ports/ARMCM3-STM32F103/port.dox b/ports/ARMCM3-STM32F103/port.dox
index 74a9c3289..3e3544ee5 100644
--- a/ports/ARMCM3-STM32F103/port.dox
+++ b/ports/ARMCM3-STM32F103/port.dox
@@ -39,7 +39,18 @@
  * - Output latched regardless of the pad setting.
  * - Direct read of input pads regardless of the pad setting.
  * .
- * <h2>Undesiderable Behavior</h2>
+ * <h2>Supported Setup Modes</h2>
+ * - @p PAL_MODE_RESET.
+ * - @p PAL_MODE_UNCONNECTED.
+ * - @p PAL_MODE_INPUT.
+ * - @p PAL_MODE_INPUT_PULLUP.
+ * - @p PAL_MODE_INPUT_PULLDOWN.
+ * - @p PAL_MODE_OUTPUT_PUSHPULL.
+ * - @p PAL_MODE_OUTPUT_OPENDRAIN.
+ * .
+ * Any attempt to setup an invalid mode is ignored.
+ *
+ * <h2>Suboptimal Behavior</h2>
  * Some GPIO features are less than optimal:
  * - Pad/group/port toggling operations are not atomic.
  * - Pad/group mode setup is not atomic.
diff --git a/ports/MSP430/port.dox b/ports/MSP430/port.dox
index e91670709..1d0216d3c 100644
--- a/ports/MSP430/port.dox
+++ b/ports/MSP430/port.dox
@@ -98,16 +98,19 @@
  * - Output latched regardless of the pad setting.
  * - Direct read of input pads regardless of the pad setting.
  * .
- * The only non atomic operations are bus/group writing and pads/group/bus
- * setup.<br>
- * The supported setup modes are:
+ * <h2>Supported Setup Modes</h2>
  * - @p PAL_MODE_RESET.
  * - @p PAL_MODE_UNCONNECTED.
  * - @p PAL_MODE_INPUT.
  * - @p PAL_MODE_OUTPUT_PUSHPULL.
  * .
- * The macros for the other modes are disabled, any attempt to setup an invalid
- * mode is ignored.
+ * Any attempt to setup an invalid mode is ignored.
+ *
+ * <h2>Suboptimal Behavior</h2>
+ * Some MSP430 I/O ports features are less than optimal:
+ * - Bus/group writing is not atomic.
+ * - Pad/group mode setup is not atomic.
+ * .
  * @ingroup MSP430_DRIVERS
  */