6-7 one-shot pulse output function, One-shot pulse output function – Omron HOME SECURITY SYSTEM - MOTION SENSOR FQM1-MMA21 User Manual

Page 199

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176

Pulse Outputs

Section 7-6

Formula:
Actual frequency = Clock frequency

÷ INT (clock frequency/target frequency)

Note INT (clock frequency/target frequency) is the dividing ratio.

The difference between the target frequency and the actual frequency
increases at higher frequencies. The following tables shows examples for a
clock frequency of 20 MHz.

7-6-7

One-shot Pulse Output Function

The one-shot pulse output function turns ON the output only for a specified
time between 0.01 and 9,999 ms. Use the STIM(980) instruction to start the
pulse output (turn the output from OFF to ON). After the time specified in
STIM(980) has elapsed, the pulse output is automatically turned OFF (in the
hardware).

Target frequency (Hz)

Actual output frequency

952,382 to 1,000,000

1,000,000

909,092 to 952,381

952,381

869,566 to 909,091

909,091

.
.
.

.
.
.

487,806 to 500,000

500,000

476,191 to 487,805

487,805

465,117 to 476,190

476,190

.
.
.

.
.
.

198,021 to 200,000

100,806

196,079 to 198,020

198,020

194,176 to 196,078

196,078

.
.
.

.
.
.

49,876 to 50,000

50,000

49,752 to 49,875

49,875

4,929 to 49,751

49,751

.
.
.

.
.
.

402

402

401

401

400

400

Dividing circuit

Output pulses

(Actual output frequency)

Integer dividing ratio set
according to the target
frequency set by user.

Clock-generated pulses
(one of four possible settings)

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