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+Name: Generic Clock (compatible)
+ID: 0x12d0b402
+Version: 1
+
+Interrupts do different things depending on contents of the A register:
+
+ A | BEHAVIOR
+---+----------------------------------------------------------------------------
+ 0 | The B register is read, and the clock will tick 60/B times per second.
+ | If B is 0, the clock is turned off.
+ 1 | Store number of ticks elapsed since last call to 0 in C register
+ 2 | If register B is non-zero, turn on interrupts with message B. If B is zero,
+ | disable interrupts
+---+----------------------------------------------------------------------------
+
+When interrupts are enabled, the clock will trigger an interrupt whenever it
+ticks.