
125
μPD780948, μPD78F0948, μPD780949, μPD78F0949
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 the capture/
compare control register 0.
When using CR00 as compare register
The value set to CR00 is always compared with the count value of the 16-bit timer register (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 includes 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 edge of TI00
and TI01 is performed via the prescaler mode register 0 (PRM0).
Tables 7-2 and 7-3 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 7-2: Valid Edge of TI00 Pin and Valid Edge of Capture Trigger of Capture/Compare Register
Table 7-3: Valid Edge of TI01 Pin and Valid Edge of Capture Trigger of Capture/Compare Register
CR00 is set by a 16-bit memory manipulation instruction.
After RESET input, the value of CR00 is undefined.
Caution:
Set a value other than 0000H in CR00. This means, that an 1-pulse count operation
cannot be performed when CR00 is used as an event counter.
ES01
0
0
1
1
ES00
0
1
0
1
Valid Edge of TI00 Pin
Falling edge
Rising edge
Setting prohibited
Both rising and falling edges
Capture Trigger of CR00
Rising edge
Falling edge
Setting prohibited
No capture operation
ES01
0
0
1
1
ES00
0
1
0
1
Valid Edge of TI00 Pin
Falling edge
Rising edge
Setting prohibited
Both rising and falling edges
Capture Trigger of CR00
Rising edge
Falling edge
Setting prohibited
Both rising and falling edges