AVIIVA® EM1
43
1043D - AVIIVA EM1 –04/11
e2v semiconductors SAS 2011
6.3.9
CounterAndTimerControl
This section lists all features that relates to
control and monitoring of Counters and Timers.
A Counter is used to count internal events
(FrameStart, FrameTrigger, …), I/O external
events (Input Line rising edge, …) and even clock
ticks. It can be Reset or Read at anytime.
Counters and Timers can also be cascaded to
increase their range if necessary.
Timers are readable and can be used to measure
the duration of internal or external signals. A
Timer can also be used to generate a timed
strobe pulse with an optional delay before
activation.
In AVIIVA EM1 camera, 2 x Counters and 2 x
Timers are available and are used in different
applications:
¾
A Counter is used to count internal events.
Ex: number of frame trigger, number of line
started…
¾
A timer is used to measure the duration from
an event. Ex: starts the Frame Acquisition
200µs after the reception of a Frame
Trigger.
•
Counter
:
To start counter there are several possibilities:
¾
There is no condition to start the counter (
CounterTriggerSource = Off
), the counter increment
each time the event occurs.
¾
There is a condition on the start of the counter: this condition has to be selected in the enumeration
of the
CounterTriggerSource
feature and the activation with
CounterTriggerActivation
feature.
The counter stops incrementing if :
¾
The
CounterDuration
feature is equal to the CounterValue, even if a new event selected occur no new
increment of the counter and no reset happened.
¾
A Reset happened either due to the
CounterReset
command (Enable with
CounterResetSource
=Software) or due to an external event happened on Inputs (Enable with
CounterTriggerSource
and
CounterTriggerActivation
features). If a new event happens the counter
starts from 0 to count if condition of start is true.
