Meilhaus Electronic ME-1400, Электронное руководство

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3.3.2 Clock Output and Interrupt Control
Note: The clock output is not supported by the ME-iDS at the
moment!
The pin labelled „OSC/IR_IN“ resp. „IR_IN“ is the interrupt input by
default. Alternatively a system independent symmetrical clock
generated by the on-board crystal oscillator can be output (1 MHz
or 10 MHz).
OSC:
Oscillator Clock Output - this signal connects the internal
oscillator clock signal (1 MHz or 10 MHz) with the D-Sub
connector. This functionality is only supported by the ME-
iDS under Linux at the moment!
IR_IN: IRQ Input - a rising edge at this pin will cause an
interrupt. If IR_IN is held high or not connected, the IR IN
is ignored.
Configuration is done by software. For programming please read
chapter 4.2 on page 18. The interrupt logic is disabled after
power-up and must be enabled before using by software.
Model Function Default Setting
ME-1400 n.c. –
–
ME-1400E n.c. –
ME-1400A (OSC)/IR_IN IR_IN
by software
ME-1400EA (OSC)/IR_IN IR_IN
ME-1400B (OSC)/IR_IN IR_IN
by software
ME-1400EB (OSC)/IR_IN IR_IN
3.3.3 Pulse Width Modulation
A special application for the counters is the so-called pulse width
modulation (PWM). With proper external wiring (see diagram 4) the
3 counters of each counter component can be used together to
create an output signal with a variable duty cycle. The duty cycle
can be set between 1…99 % in 1 % steps. The base clock can be
sourced either by an external frequency generator (max.10 MHz)
or by the internal crystal oscillator (1 MHz or 10 MHz). This