NEC PD78078 用户手册

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CHAPTER 10 8-BIT TIMER/EVENT COUNTERS 5 AND 6

10.4.3 Square-wave output

A square wave with any selected frequency is output at intervals of the value preset to 8-bit compare registers

(CR50 and CR60).

The TO5/P100/TI5 or TO6/P101/TI6 pin output status is reversed at intervals of the count value preset to CR50

or CR60 by setting bit 1 (TMC51) and bit 0 (TOE5) of the 8-bit timer output control register 5 (TMC5), or bit 1 (TMC61)

and bit 0 (TOE1) of the 8-bit timer mode control register 6 (TMC6) to 1.

This enables a square wave of any selected frequency to be output.

Figure 10-12. 8-Bit Timer Mode Control Register Settings for Square-Wave Output Operation

Caution When TI5/P100/TO5 or TI6/P101/TO6 pin is used as the timer output, set port mode register

(PM100 or PM101) and output latch (P100 or P101) to 0.

Remark

n = 5, 6

Figure 10-13. Timing of Square Wave Output Operation

Note

The initial value of the TOn output can be set by bits 2 and 3 (LVSn and LVRn) of the 8-bit timer output

control register n (TOCn).

Remark

n = 5, 6

TCEn

TMCn6

0/1

LVSn LVRn TMCn1 TOEn

TMCn

0/1

TOn output enable

Inversion of output on match of TMn and CRn0

Specifies TO0 output F/F1 initial value

Clear and start mode on match of TMn and CRn0

TMn operation enable

Count Clock

TMn Count Value

N–1

Count Start

CRn0

TOn

Note