UPD784026 Renesas Electronics Corporation., UPD784026 Datasheet - Page 334

• Manufacturer Part Number: UPD784026
• Description: 16/8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

10.7.2 Capture Operations
register in synchronization with an external trigger, and retained there.
trigger (capture trigger). The count value of TM2 in the process of being counted in synchronization with the capture trigger
is fetched into the capture register (CR22) in synchronization with INTP1, or into the capture/compare register (CR21) when
a capture operation is specified in synchronization with INTP2, and is retained there.
generated.
edges are set as capture triggers, the width of pulses input from off-chip can be measured, and if a capture trigger is
generated by a single edge, the input pulse cycle can be measured.
by capture triggar to CR21 or CR22.
294
Remark CLR22 = 0
Timer/counter 2 performs capture operations in which the timer register 2 (TM2) count value is fetched into the capture
A valid edge detected from the input of the external interrupt request input pins (INTP1/INTP2) is used as the external
The contents of CR21 and CR22 are retained until the next capture triggers corresponding to CR21 and CR22 are
The capture trigger valid edge is set by means of external interrupt mode register 0 (INTM0). If both rising and falling
See Figure 19-1 in CHAPTER 19 EDGE DETECTION FUNCTION for details of the INTM0 format.
When CR21 is used as a capture register, TM2 can be cleared as soon as the contents of TM2 have been captured
Interrupt Request
Interrupt Request
TO2 Pin Output
TO3 Pin Output
ENTO2 1
ENTO3 1
TM2
Count Value
ALV3 1
ALV2 1
INTC20
INTC21
OVF2
0H
Count Start
CE2
CLR21
Figure 10-17 TM2 Clearance after Match Detection
Inactive Level
Inactive Level
1
0
CR21
CHAPTER 10 TIMER/COUNTER 2
CR20
FFH
Count Disabled
CE2
Cleared by Software
0
Count Start
CE2
CLR21
1
1
CR21
Clear
CR21
Clear