Data Translation DT9834 Series, User Manual

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Chapter 5
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Digital output – For digital output operations, enter the digital output port (all 16
digital output lines) as channel 4 in the output channel list; refer to page 90 for more
information. The output clock (internal or external) paces the update of the digital
output port (as well as the update of the analog output channels); refer to
page 91 for
more information.
• Interrupt-on-change operations – You can use the Open Layers Control Panel applet to
select any of the first eight digital input lines to perform interrupt-on-change operations;
refer to
page 33 for more information.
When any one of the specified digital input lines changes state, the module reads the
entire 16-bit digital input value and generates an interrupt. Using software, you can
determine which digital input lines change state and the current value of the digital input
port.
Note: If you are using the DataAcq SDK to perform a continuous digital input operation,
use the lParam parameter of the olDaSetWndHandle or olDaSetNotificationProcedure
function to determine which digital input line changed state and the status of the digital
input port when the interrupt occurred.
The low byte of the first word of lParam contains the state of the digital input subsystem,
where bit 0 corresponds to digital input line 0 and bit 7 corresponds to digital input line 7.
The high byte of the first word of lParam contains the digital lines (bits) that changed state
causing the interrupt to occur, where bit 8 corresponds to digital input line 0 and bit 15
corresponds to digital input line 7.
• Dynamic digital output is useful for synchronizing and controlling external equipment
and allows you to output data to the dynamic digital output line each time an analog
input value is acquired. This mode is supported by the DataAcq SDK (not by the DT-Open
Layer for .NET Class Library) and is programmed through the analog input subsystem;
refer to
page 82 for more information.