Chapter 7 16-bit Timer

7-7 16-bit High Precision PWM Output

(Cycle/Duty can be changed consecutively)

The TM7IO pin outputs high precision PWM output, which is determined by the match timing of the timer binary counter and the compare register 1 and the match timing of the binary counter and the compare register 2.

7-7-1 Operation

„16-bit High Precision PWM Output Operation (Timer 7)

The PWM waveform with any cycle/duty is generated by setting the cycle of PWM to the compare register 1 (TM7OC1) and setting the duty of the "H" period to the compare register 2 (TM7OC2). The 16- bit timer that high precision PWM output operation function can be used is timer 7.

„Count Timing of High Precision PWM Output (at Normal) (Timer 7)

Count clock

TM7EN flag

Compare register 1

Compare register 2

Binary counter

PWM source waveform

TM7IO output (PWM output)

N

M

0000 0001

M-1 M M+1 M+2

N-1 N 0000 0001

M-1 M M+1

(A)

(B)

(C)

 

Set time in the compare register 2

 

 

PWM basic component (Set time in the compare register 1)

 

Figure 7-7-1 Count Timing of High Precision PWM Output (at Normal)

PWM source waveform,

(A)is "H" until the binary counter reaches the compare register from x'0000'.

(B)is "L" after the TM7OC2 compare match, then the binary counter counts up till the binary counter reaches the TM7OC1 compare register to be cleared.

(C)is "H", again if the binary counter is cleared.

The PWM output from pin is 1 count clock delay of PWM source waveform. This is happened to form inside to correct the output cycle.

16-bit High Precision PWM Output VII - 27

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Panasonic F77G, MN101C77C user manual bit High Precision PWM Output, Cycle/Duty can be changed consecutively