User manual

Counter
After startup of CEBO-STICK, the multifunction IO-0 is configured as digital input signal.
To use the counter functionalities, the corresponding peripheral needs to be enabled
first. This is done by software calls (API). While IO-0 is used as counter input, digital IO
functionalities or trigger input / output are not available.
Counter input
In counter input mode, each counter event on IO-0 causes the firmware to jump to a
small interrupt routine and increment an internal 32bit register. Thus maximum input
edge rate without missing counts depends on available processing resources. When
IO-0 counter module is used exclusively, maximum edge rate will be in the range of
TBD edges / s. With Multi Frame DAQ enabled at the same time, maximum input edge
rate will be less. And since each counter event needs processing time, maximum Multi
Frame DAQ input frame rate will be reduced, too.
CEBO-STICK can be configured for three different types of counter input signals: rising
edge, falling edge or alternating.
Rising edge mode
In rising edge mode, every transition from low to high level on terminal IO-0 increments
the counter value.
Falling edge mode
In falling edge mode, every transition from high to low level on terminal IO-0 increments
the counter value.
Alternating mode
In alternating mode, both edges increment the counter value.
Counter input
Parameter Condition Min.
3
Typ. Max.
3
Unit
Low level input voltage 0,0 0,8 Volts
High level input voltage 2,0 5,0 Volts
Maximum input voltage range
4,,5
-1,0 6,5 Volts
Input total edge rate Read after counting
10
tbd Edges/s
Polling tbd Edges/s
Multi frame DAQ
11
tbd Edges/s
10 Counter value is checked only after counter is disabled.
11 Input frame includes analog input 0 and counter value.
CEBO-STICK Reference Manual Cesys GmbH
[ v1.1 ] 12/28