UPD78F0537DGA(T)-9EV-A NEC, UPD78F0537DGA(T)-9EV-A Datasheet - Page 239

• Manufacturer Part Number: UPD78F0537DGA(T)-9EV-A
• Description: 8BIT MCU, 128K FLASH, 7KB RAM, SMD
• Manufacturer: NEC

Specifications of UPD78F0537DGA(T)-9EV-A

• Controller Family/series: UPD78
• No. Of I/o's: 55
• Ram Memory Size: 7KB
• Cpu Speed: 20MHz
• No. Of Timers: 8
• No. Of Pwm: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 128KB
• Oscillator Type: External, Internal

(2) Measuring the pulse width by using one input signal of the TI00n pin (free-running timer mode)
Capture trigger input
Capture trigger input
(TMC0n3, TMC0n2)
Set the free-running timer mode (TMC0n3 and TMC0n2 = 01). The count value of TM0n is captured to CR00n in
the phase reverse to the valid edge detected on the TI00n pin. When the valid edge of the TI00n pin is detected,
the count value of TM0n is captured to CR01n.
By this measurement method, values are stored in separate capture registers when a width from one edge to
another is measured. Therefore, the capture values do not have to be saved. By subtracting the value of one
capture register from that of another, a high-level width, low-level width, and cycle are calculated.
If an overflow occurs, the value becomes negative if one captured value is simply subtracted from another and,
therefore, a borrow occurs (bit 0 (CY) of the program status word (PSW) is set to 1). If this happens, ignore CY
and take the calculated value as the pulse width. In addition, clear bit 0 (OVF0n) of 16-bit timer mode control
register 0n (TMC0n) to 0.
Remark n = 0:
Capture interrupt
Capture interrupt
Capture register
Capture register
TM0n register
Operable bits
Overflow flag
(INTTM01n)
(INTTM00n)
(OVF0n)
(CR00n)
(CR01n)
n = 0, 1:
FFFFH
(TI00n)
(TI01n)
0000H
µ
µ
0000H
L
L
PD78F0531, 78F0532, 78F0533
PD78F0534, 78F0535, 78F0536, 78F0537, 78F0537D
Figure 7-54. Timing Example of Pulse Width Measurement (2)
00
0000H
CHAPTER 7 16-BIT TIMER/EVENT COUNTERS 00 AND 01
A
• TMC0n = 04H, PRM0n = 10H, CRC0n = 07H
01
M
A
User’s Manual U17260EJ6V0UD
B
M
0 write clear
N
B
N
C
0 write clear
S
C
D
S
0 write clear
P
D
P
E
0 write clear
Q
E
Q
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