UPD78F0138 NEC, UPD78F0138 Datasheet - Page 167

• Manufacturer Part Number: UPD78F0138
• Description: (UPD78xxxx) 8-Bit Single-Chip Microcontrollers
• Manufacturer: NEC

(1) Pulse width measurement with free-running counter and one capture register
Remark 0/1: Setting 0 or 1 allows another function to be used simultaneously with pulse width measurement.
When 16-bit timer counter 0n (TM0n) is operated in free-running mode, and the edge specified by prescaler mode
register 0n (PRM0n) is input to the TI00n pin, the value of TM0n is taken into 16-bit timer capture/compare
register 01n (CR01n) and an external interrupt request signal (INTTM01n) is set.
Specify both the rising and falling edges by using bits 4 and 5 (ES0n0 and ES0n1) of PRM0n.
Sampling is performed using the count clock selected by PRM0n, and a capture operation is only performed
when a valid level of the TI00n pin is detected twice, thus eliminating noise with a short pulse width.
Figure 6-22. Control Register Settings for Pulse Width Measurement with Free-Running Counter
n = 0:
n = 0, 1:
See the description of the respective control registers for details.
TMC0n
PRM0n
CRC0n
and One Capture Register (When TI00n and CR01n Are Used)
µ
µ
PD780131, 780132
PD780133, 780134, 78F0134, 780136, 780138, 78F0138
ES1n1
CHAPTER 6 16-BIT TIMER/EVENT COUNTERS 00 AND 01
0/1
7
0
7
0
(a) 16-bit timer mode control register 0n (TMC0n)
(b) Capture/compare control register 0n (CRC0n)
ES1n0
0/1
6
0
6
0
(c) Prescaler mode register 0n (PRM0n)
ES0n1
5
0
5
0
1
User’s Manual U16228EJ2V0UD
ES0n0
4
0
4
0
1
TMC0n3
0
3
0
3
0
TMC0n2
CRC0n2
1
1
2
0
TMC0n1
CRC0n1
PRM0n1
0/1
0/1
0/1
OVF0n
CRC0n0
PRM0n0
0/1
0
0
Free-running mode
CR00n used as compare register
CR01n used as capture register
Selects count clock (setting “11” is prohibited).
Specifies both edges for pulse width detection.
Setting invalid (setting “10” is prohibited.)
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