Pc Card I/O Channel Interface Circuitry - DAQ DAQCard-1200 User Manual

Chapter 4 Theory of Operation

PC Card I/O Channel Interface Circuitry

Address Bus
Control Lines
Data Bus
IRQ
DAQCard-1200 User Manual
The major components of the DAQCard-1200 are as follows:
• PC Card I/O channel interface circuitry
• AI circuitry
• AO circuitry
• DIO circuitry
• Timing circuitry
• Calibration circuitry
The internal data and control buses interconnect the components. The rest
of the chapter explains the theory of operation of each of the
DAQCard-1200 components.
The DAQCard-1200 PC Card I/O channel interface circuitry is shown in
Figure 4-2 and consists of an address bus, a data bus, interrupt lines, and
several control and support signals.
Timing
Interface
Data
Buffers
Interrupt
Control
Figure 4-2. PC Card I/O Interface Circuitry Block Diagram
Address
Decoder
Card
Information
PCMCIA
Control
4-2
Register Selects
Read and Write Signals
Internal Data Bus
Interrupt Requests
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