Putting updated HardwareTimer back into the build.

HardwareTimer was removed from the build when the timer refactor was
done; this redoes it in terms of the new timer.h interface.  A variety
of conflicting or badly designed bits were deprecated or removed.

I'm still not satisfied with this interface, as it's going to make
life difficult moving forward to high-density chips, where the
addition of basic timers means that the capture/compare methods won't
apply in some cases.  However, we need to get 0.0.10 out the door, so
it'll have to do for now.

The docs are up to date, and contain a warning that the Wirish API
isn't stable and a recommendation to use libmaple proper.

1 files changed, 10 insertions, 0 deletions

diff --git a/docs/source/timers.rst b/docs/source/timers.rst
index cb30081..9163e69 100644
--- a/docs/source/timers.rst
+++ b/docs/source/timers.rst
@@ -45,6 +45,16 @@ event" interrupt is generated.  You can configure the Maple to notify
 you when this takes place, by registering an interrupt handler, which
 is a function that will be called when the update event occurs.
 
+By default, different compare values only change the relative offsets
+between events on a single timer ("phase").  They don't control the
+frequency with which they occur.  However, a common trick is to
+increment the compare value manually in the interrupt handler so that
+the event will fire again after the increment period.  There can be a
+different increment value for each channel, so this trick allows
+events to be programmed at 4 different rates on a single timer.  Note
+that function call overheads mean that the smallest increment rate is
+at least a few microseconds.
+
 Function Reference
 ------------------