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PULSE_WIDTH

The minimal width for pulse counting is specified in μs . It describes the

minimum duration of an event that occurs on one of the four inputs. Any noise

that appears during this time span is supressed and not counted. Valid

configurations for PULSE_WIDTH are 32 μs to 65534 μs.

PULSE_CH

This register selects the input on which events are counted. Setting a value

other than 0 will start the impuls counter, immedeately.

Channel Events counted on

0 none

1 A1

2 A2

3 A3

4 A4

Read-only input registers

0x0000 FREQ_CH1 0x0004 COUNTER_H

0x0001 FREQ_CH2 0x0005 COUNTER_L

0x0002 FREQ_CH3

0x0003 FREQ_CH4

Table 4: Input registers

FREQ_CH1/2/3/4

These input registers hold frequencies detected on A1/2/3/4. Data is updated

secondly as long as START in holding register CNT_CTRL is set.

COUNTER_H/L

This pair of input registers stores the number of events counted by the impuls

counter that occurred since enabling the selected channel in PULSE_CH. The

counter value is calculates as:

event

= COUNTER_H * 65536 + COUNTER_L

Changing the selected channel will reset the counter.

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