16-Bit Timer/Event Counter Operations; Interval Timer Operations - NEC mPD780208 Subseries User Manual

6.5 16-Bit Timer/Event Counter Operations

6.5.1 Interval timer operations

By setting bits 2 and 3 (TMC02 and TMC03) of the 16-bit timer mode control register (TMC0) to 1, 1, the 16-bit
timer/event counter operates as an interval timer. Interrupt requests are generated repeatedly using the count value
set in the 16-bit compare register (CR00) beforehand as the interval.
When the count value of the 16-bit timer register (TM0) matches the value set to CR00, counting continues with
the TM0 value cleared to 0 and the interrupt request signal (INTTM0) is generated. CR00 should be set to a value
other than 0000H.
The count clock of the 16-bit timer/event counter can be selected using bits 4 to 6 (TCL04 to TCL06) of timer clock
select register 0 (TCL0).
For the operation when the value of the compare register is changed during timer count operation, refer to 6.6 16-
Bit Timer/Event Counter Operating Precautions (3).
f
X
f /2
X
2
f /2
X
3
f /2
X
TI0/P00/INTP0
CHAPTER 6 16-BIT TIMER/EVENT COUNTER
Figure 6-10. Interval Timer Configuration Diagram
16-bit compare
register (CR00)
16-bit timer register (TM0)
User's Manual U11302EJ4V0UM
INTTM0
OVF0
Clear
circuit
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