NEC 78K0S/KA1+ User Manual page 84

(1) 16-bit timer counter 00 (TM00)
TM00 is a 16-bit read-only register that counts count pulses.
The counter is incremented in synchronization with the rising edge of the count clock. If the count value is read
during operation, input of the count clock is temporarily stopped, and the count value at that point is read.
Address: FF12H, FF13H
Symbol
7
TM00
The count value is reset to 0000H in the following cases.
<1> At reset input
<2> If TMC003 and TMC002 are cleared
<3> If the valid edge of TI000 is input in the clear & start mode entered by inputting the valid edge of TI000
<4> If TM00 and CR000 match in the clear & start mode entered on a match between TM00 and CR000
<5> If OSPT00 is set to 1 in the one-shot pulse output mode
Cautions 1. Even if TM00 is read, the value is not captured by CR010.
2. When TM00 is read, count misses do not occur, since the input of the count clock is
temporarily stopped and then resumed after the read.
(2) 16-bit timer capture/compare register 000 (CR000)
CR000 is a 16-bit register which has the functions of both a capture register and a compare register. Whether
it is used as a capture register or as a compare register is set by bit 0 (CRC000) of capture/compare control
register 00 (CRC00).
CR000 is set by 16-bit memory manipulation instruction.
A reset signal generation clears CR000 to 0000H.
Figure 6-3. Format of 16-Bit Timer Capture/Compare Register 000 (CR000)
Address: FF14H, FF15H
Symbol
7
CR000
• When CR000 is used as a compare register
The value set in CR000 is constantly compared with the 16-bit timer/counter 00 (TM00) count value, and an
interrupt request (INTTM000) is generated if they match. It can also be used as the register that holds the
interval time then TM00 is set to interval timer operation.
• When CR000 is used as a capture register
It is possible to select the valid edge of the TI000 pin or the TI010 pin as the capture trigger. Setting of the
TI000 or TI010 valid edge is performed by means of prescaler mode register 00 (PRM00) (refer to Table 6-
2).
84
CHAPTER 6 16-BIT TIMER/EVENT COUNTER 00
Figure 6-2. Format of 16-Bit Timer Counter 00 (TM00)
After reset: 0000H
FF13H
6 5 4 3 2 1
After reset: 0000H
FF15H
6 5 4 3 2 1
User's Manual U16898EJ3V0UD
R
FF12H
0 7 6 5 4
R/W
FF14H
0 7 6 5 4
3 2 1 0
3 2 1 0