Omega 1002 manual A/D Conversion, Cpu

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4.4 A/D Conversion

An A/D conversion can be initiated three different ways: software command, internal programmable interval timer or external trigger. At the end of the A/D conversion, it is possible to transfer the data by polling a status register and reading the data when ready or by generating a hardware interrupt and an interrupt service routine. All modes are selected by a control register on the OME-PCI-1002 and are supported by the utility software.

Below are key points for successfully collecting A/D data:

zA/D data register, BASE+30h, stores the A/D conversion data.

zA/D data conversion ready register, BASE +10h. Check if A/D data is ready.

zA/D gain control register, BASE+14h, select gain.

zA/D multiplexer control register, BASE+10h, select analog input channel.

zA/D mode control register, BASE+0Ch, select trigger type and transfer type.

zA/D software trigger control register, BASE+1Ch.

zJP1 select single-ended or differential input.

z3 Triggers: Software, Pacer, and External trigger.

z2 Transfer Modes: Polling and Interrupt.

The block diagram is given follows:

 

16/8 to 1

Gain

12 bits

 

 

CN3

Multi-

Control

A/D

Buffer

Memory

 

plexer

 

 

 

 

 

BASE+10h

BASE+14h

Trigger

BASE+30h

CPU

 

 

 

Logic

 

 

 

 

 

BASE+1Ch

 

 

 

 

 

Software Trigger

 

 

OME-PCI-1002H/L

 

 

 

 

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Contents User’sGuide Servicing North America Table of Contents Software and Demo Program Diagnostic Program Introduction General DescriptionBlock Diagram X86 SystemFeatures Analog Inputs SpecificationsPower Consumption 3 D/I and D/O 4 A/D Trigger MethodsProgrammable Timer/Counter Interrupt ChannelApplications OME-PCI-1002 series multifunction cardsProduct Check List Release NotesHardware Configuration Board LayoutJumper Setting A/D CalibrationSystem Block Diagram OME-PCI-1002 System Function BlockDaughter Boards OME-DB-8225 OME-DB-37OME-DB-16P Isolated Input Board OME-DB-16R Relay Board Analog Input Signal Connection Page Page Signal Shielding Jumper Settings Connectors Page How to Find the I/O Address O RegistersPage I/O Address Map Section 8254 Registers Status Register Clear Interrupt General Control Register Interrupt Source SelectionTrigger Method Selection Function Operation Digital I/O8254 Timer A/D triggerSymbol Name Minimum Maximum A/D Conversion CPUSuggested Settling Times 1 A/D Conversion Trigger Modes Software Trigger and Polling Techniques Page Page Software and Demo Program Power-ON Plug & Play Test Driver Plug & Play TestD I/O Test A/D TestWARRANTY/DISCLAIMER Temperature