Kontron PCI-AOB16/12, Руководство пользователя

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PCI-AOB8/12 (16/12) User’s Guide
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Analog Output Update
Analog outputs are updated under program control in any of three ways:
J Automatic Update:
Each channel is updated individually when new data are
written to the related high-byte base address. Individual update mode may be set
by a special read operation as defined in the programming section of this manual.
J Simultaneous Update:
The outputs of all D/As may be updated simultaneously.
This is done by first enabling simultaneous updating for all outputs, preloading
the low and high bytes of each DAC, and then initiating a simultaneous update by
software command.
J Timer Update: The counter/timer can initiate updates. First, disable interrupts
and updates (read base+4 and read base+6) and enable Simultaneous Updates
(read base+0). Then write the initial values into the DACs. Program the counter/
timer for the tick frequency (mode 2 or mode 4), initialize your ISR, enable
updates (read base+5), and enable interrupts (read base+3). This
counter-generated update pulse is available at the 40-pin header connector
(OUT2) to synchronize external devices.
Refer to Chapter 5, “Programming” of this manual for more detail.