timers
******

This module exposes the GBA's 4 hardware timers.

Each timer holds a 16-bit value which ticks up by 1 after a certain number
of CPU cycles (determined by the the timer's frequency setting).

When this value overflows, it will reset to the timer's `start` value and
an interrupt will be raised if one has been requested.

**Example:**

.. code-block:: nim

   import natu/[irq, timers, mgba]
   
   proc myHandler() =
     mgba.printf("Bonk!")
   
   irq.put(iiTimer3, myHandler)      # Register the handler.
   
   tmcnt[3].init(
     freq = tf16kHz,
     start = cast[uint16](-0x4000),  # 2^14 ticks at 16 kHz = 1 second
     active = true,                  # Enable the timer.
     irq = true,                     # Fire an interrupt when the timer overflows.
   )

.. note::
   Timer 0 is used by :doc:`maxmod` for audio, so don't touch it
   unless you know what you're doing.

-----------------------------

Types
=====

.. autonim:: timers.TimerFreq
.. autonim:: timers.Timer

-----------------------------

I/O Registers
=============

.. autonim:: timers.tmcnt
.. autonim:: timers.count
.. autonim:: timers.`start=`
.. autonim:: timers.init
.. autonim:: timers.edit

-----------------------------

Profiling Helpers
=================

These procedures allow you to measure exactly how many CPU cycles a section of code takes to execute.

.. autonim:: timers.profileStart
.. autonim:: timers.profileStop