NEC 78014Y Series, User Manual

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CHAPTER 8 16-BIT TIMER/EVENT COUNTER
8.5.5 Square-wave output operation
The 16-bit timer/event counter operates as a square wave with any selected frequency which is output at intervals
of the count value preset to the 16-bit compare register (CR00).
The TO0/P30 pin output status is inverted at intervals of the count value preset to CR00 by setting bit 0 (TOE0)
and bit 1 (TOC01) of the 16-bit timer output control register to 1. This enables a square wave with any selected
frequency to be output.
Table 8-6. 16-Bit Timer/Event Counter Square-Wave Output Ranges
TCL06 TCL05 TCL04 Minimum Pulse Width Maximum Pulse Width Resolution
0 0 0 2
×
TI0 input cycle 2 16
×
TI0 input cycle TI0 input edge cycle
0 1 0 2 2
×
1/f
X
(400 ns) 2 17
×
1/f
X
(13.1 ms) 2
×
1/f
X
(200 ns)
0 1 1 2
3
×
1/f
X
(800 ns) 2
18
×
1/f
X
(26.2 ms) 2
2
×
1/f
X
(400 ns)
1 0 0 2 4
×
1/f
X
(1.6
µ
s) 2 19
×
1/f
X
(52.4 ms) 2 3
×
1/f
X
(800 ns)
Remarks 1. f
X
: Main system clock oscillation frequency
2. TCL04 to TCL06: Bit 4 to bit 6 of timer clock select register 0 (TCL0)
3. Values in parentheses apply to operation with f
X
= 10.0 MHz
Figure 8-19. Square-Wave Output Operation Timings
Note Initial value of TO0 output can be set at bits 2 and 3 (LVR0 and LVS0) of the 16-bit timer output control register
(TOC0).
Count Start
Count Clock
TM0 Count Value
CR00
TO0 Note
0000 0001 0002 N – 1 N 0000 0001 0002 N – 1 N 0000
N N