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CHAPTER 6 16-BIT TIMER/EVENT COUNTER 00
Preliminary User’s Manual U16846EJ1V0UD
132
6.4.5 Square-wave output operation
Setting
The basic operation setting procedure is as follows.
<1> Set the count clock by using the PRM00 register.
<2> Set the CRC00 register (see Figure 6-29 for the set value).
<3> Set the TOC00 register (see Figure 6-29 for the set value).
<4> Set any value to the CR000 register (0000H cannot be set).
<5> Set the TMC00 register to start the operation (see Figure 6-29 for the set value).
Caution CR000 cannot be rewritten during TM00 operation.
Remarks 1. For the setting of the TO00 pin, see 6.3 (5) Port mode register 0 (PM0).
2. For how to enable the INTTM000 interrupt, see CHAPTER 14 INTERRUPT FUNCTIONS.
A square wave with any selected frequency can be output at intervals determined by the count value preset to 16-
bit timer capture/compare register 000 (CR000).
The TO00 pin output status is reversed at intervals determined by the count value preset to CR000 +1 by setting
bit 0 (TOE00) and bit 1 (TOC001) of 16-bit timer output control register 00 (TOC00) to 1. This enables a square wave
with any selected frequency to be output.
Figure 6-29. Control Register Settings in Square-Wave Output Mode (1/2)
(a) 16-bit timer mode control register 00 (TMC00)
7
0
6
0
5
0
4
0
TMC003
1
TMC002
1
TMC001
0
OVF00
0
TMC00
Clears and starts on match between TM00 and CR000.
(b) Capture/compare control register 00 (CRC00)
7
0
6
0
5
0
4
0
3
0
CRC002
0/1
CRC001
0/1
CRC000
0
CRC00
CR000 used as compare register