Section 18 Multi-Function Timer Pulse Unit (MTU)
Rev. 4.00 Sep. 14, 2005 Page 562 of 982
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18.3.17 Bus Master Interface
The timer counters (TCNT), general registers (TGR), timer subcounter (TCNTS), timer period
buffer register (TCBR), and timer dead time data register (TDDR), and timer period data register
(TCDR) are 16-bit registers. A 16-bit data bus to the bus master enables 16-bit read/writes. 8-bit
read/write is not possible. Always access in 16-bit units.
All registers other than the above registers are 8-bit registers. These are connected to the CPU by a
16-bit data bus, so 16-bit read/writes and 8-bit read/writes are both possible.
18.4 Operation
18.4.1 Basic Functions
Each channel has a TCNT and TGR register. TCNT performs up-counting, and is also capable of
free-running operation, synchronous counting, and external event counting.
Each TGR can be used as an input capture register or output compare register.
Always set the MTU external pins function using the pin function controller (PFC).
• Counter Operation
When one of bits CST0 to CST4 is set to 1 in TSTR, the TCNT counter for the corresponding
channel begins counting. TCNT can operate as a free-running counter, periodic counter, for
example.