NEC uPD78P078 User Manual
Page 225
225
CHAPTER 9 8-BIT TIMER/EVENT COUNTERS 1 AND 2
(2) External event counter
The number of pulses of an externally input signal can be measured.
(3) Square-wave output
A square wave with any selected frequency can be output.
Table 9-2. 8-Bit Timer/Event Counters 1 and 2 Square-Wave Output Ranges
Minimum Pulse Width
Maximum Pulse Width
Resolution
MCS = 1
MCS = 0
MCS = 1
MCS = 0
MCS = 1
MCS = 0
2 x 1/f
X
2
2
x 1/f
X
2
9
x 1/f
X
2
10
x 1/f
X
2 x 1/f
X
2
2
x 1/f
X
(400 ns)
(800 ns)
(102.4
µ
s)
(204.8
µ
s)
(400 ns)
(800 ns)
2
2
x 1/f
X
2
3
x 1/f
X
2
10
x 1/f
X
2
11
x 1/f
X
2
2
x 1/f
X
2
3
x 1/f
X
(800 ns)
(1.6
µ
s)
(204.8
µ
s)
(409.6
µ
s)
(800 ns)
(1.6
µ
s)
2
3
x 1/f
X
2
4
x 1/f
X
2
11
x 1/f
X
2
12
x 1/f
X
2
3
x 1/f
X
2
4
x 1/f
X
(1.6
µ
s)
(3.2
µ
s)
(409.6
µ
s)
(819.2
µ
s)
(1.6
µ
s)
(3.2
µ
s)
2
4
x 1/f
X
2
5
x 1/f
X
2
12
x 1/f
X
2
13
x 1/f
X
2
4
x 1/f
X
2
5
x 1/f
X
(3.2
µ
s)
(6.4
µ
s)
(819.2
µ
s)
(1.64 ms)
(3.2
µ
s)
(6.4
µ
s)
2
5
x 1/f
X
2
6
x 1/f
X
2
13
x 1/f
X
2
14
x 1/f
X
2
5
x 1/f
X
2
6
x 1/f
X
(6.4
µ
s)
(12.8
µ
s)
(1.64 ms)
(3.28 ms)
(6.4
µ
s)
(12.8
µ
s)
2
6
x 1/f
X
2
7
x 1/f
X
2
14
x 1/f
X
2
15
x 1/f
X
2
6
x 1/f
X
2
7
x 1/f
X
(12.8
µ
s)
(25.6
µ
s)
(3.28 ms)
(6.55 ms)
(12.8
µ
s)
(25.6
µ
s)
2
7
x 1/f
X
2
8
x 1/f
X
2
15
x 1/f
X
2
16
x 1/f
X
2
7
x 1/f
X
2
8
x 1/f
X
(25.6
µ
s)
(51.2
µ
s)
(6.55 ms)
(13.1 ms)
(25.6
µ
s)
(51.2
µ
s)
2
8
x 1/f
X
2
9
x 1/f
X
2
16
x 1/f
X
2
17
x 1/f
X
2
8
x 1/f
X
2
9
x 1/f
X
(51.2
µ
s)
(102.4
µ
s)
(13.1 ms)
(26.2 ms)
(51.2
µ
s)
(102.4
µ
s)
2
9
x 1/f
X
2
10
x 1/f
X
2
17
x 1/f
X
2
18
x 1/f
X
2
9
x 1/f
X
2
10
x 1/f
X
(102.4
µ
s)
(204.8
µ
s)
(26.2 ms)
(52.4 ms)
(102.4
µ
s)
(204.8
µ
s)
2
11
x 1/f
X
2
12
x 1/f
X
2
19
x 1/f
X
2
20
x 1/f
X
2
11
x 1/f
X
2
12
x 1/f
X
(409.6
µ
s)
(819.2
µ
s)
(104.9 ms)
(209.7 ms)
(409.6
µ
s)
(819.2
µ
s)
Remarks 1. f
X
: Main system clock oscillation frequency
2. MCS : Bit 0 of oscillation mode selection register (OSMS)
3. Figures in parentheses apply to operation with f
X
= 5.0 MHz.