NEC mPD784225 Series User Manual page 152

(2) Capture/compare register 00 (CR00)
CR00 is a 16-bit register that functions as a capture register and as a compare register. Whether this register
functions as a capture or compare register is specified by using bit 0 (CRC00) of capture/compare control register
0.
• When using CR00 as compare register
The value set to CR00 is always compared with the count value of 16-bit timer counter 0 (TM0). When the
values of the two coincide, an interrupt request (INTTM00) is generated. When TM00 is used as an interval
timer, CR00 can also be used as a register that holds the interval time.
• When using CR00 as capture register
The valid edge of the TI00 or TI01 pin can be selected as a capture trigger. The valid edges for TI00 and
TI01 are set with prescaler mode register 0 (PRM0).
Tables 8-2 and 8-3 show the conditions that apply when the capture trigger is specified as the valid edge of
the TI00 pin and the valid edge of the TI01 pin respectively.
Table 8-2. Valid Edge of TI00 Pin and Capture Trigger of CR00
ES01 ES00
0
0
1
1
Table 8-3. Valid Edge of TI01 Pin and Capture Trigger of CR00
ES01 ES00
0
0
1
1
CR00 is set by a 16-bit memory manipulation instruction.
RESET input sets CR00 to 0000H.
Caution Set any value other than 0000H in CR00. When using the register as an event counter, a count
for one-pulse can not be operated.
152
CHAPTER 8 16-BIT TIMER/EVENT COUNTER
Valid Edge of TI00 Pin
0 Falling edge
1 Rising edge
0 Setting prohibited
1 Both rising and falling edges
Valid Edge of TI01 Pin
0 Falling edge
1 Rising edge
0 Setting prohibited
1 Both rising and falling edges
User's Manual U12697EJ3V0UM
Capture Trigger of CR00
Rising edge
Falling edge
Setting prohibited
No capture operation
Capture Trigger of CR00
Falling edge
Rising edge
Setting prohibited
Both rising and falling edges