Tektronix Using Keithley DriverLINX with KPCMCIA-PIO24-C (1.5MB) User manual

Keithley KPCMCIA-PIO24

Using DriverLINX with Your

Hardware

Information in this document is subject to change without notice. The software described is this document is furnished under a license agreement. The software may be used or copied only in accordance with the terms of the agreement.

SCIENTIFIC SOFTWARE TOOLS, INC. SHALL NOT BE LIABLE FOR ANY SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES RELATED TO THE USE OF THIS PRODUCT. THIS PRODUCT IS NOT DESIGNED WITH COMPONENTS OF A LEVEL OF RELIABILITY SUITABLE FOR USE IN LIFE SUPPORT OR CRITICAL APPLICATIONS.

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SST 15-0801-1

DriverLINX, SSTNET, and LabOBJX are registered trademarks and DriverLINX/VB is a trademark of Scientific Software Tools, Inc. MetraByte and KPCMCIA are trademarks of Keithley Instruments, Inc. Microsoft and Windows are registered trademarks and Visual C++ and Visual Basic are trademarks of Microsoft Corporation. Borland is a registered trademark and Borland C++ and Delphi are trademarks of Borland International, Inc. All other brand and product names are trademarks or registered trademarks of their respective companies.

Contents

Preface 5

Software License and Software Disclaimer of Warranty............................................................5

About DriverLINX.....................................................................................................................7

About This User’s Guide...........................................................................................................7

Conventions Used in This Manual.............................................................................................8

Configuring the KPCMCIA-PIO24 9

Introduction................................................................................................................................9

Configure DriverLINX Device Dialog.......................................................................................9

Using the KPCMCIA-PIO24 with DriverLINX 21

Introduction..............................................................................................................................21

DriverLINX Hardware Model for KPCMCIA-PIO24 .............................................................21

Connecting Signals to the KPCMCIA-PIO24..........................................................................26

Device Subsystem....................................................................................................................28

Digital Input Subsystem...........................................................................................................29

Digital Output Subsystem ........................................................................................................42

Device Subsystem Page.............................................................................................11

Digital Input Subsystem Page....................................................................................13

Digital Output Subsystem Page .................................................................................17

Counter/Timer Subsystem Page.................................................................................19

DriverLINX Subsystems............................................................................................21

DriverLINX Modes ...................................................................................................22

DriverLINX Operations and Events..........................................................................23

Logical Channels.......................................................................................................25

Buffers.......................................................................................................................25

Digital Input Subsystem Signals................................................................................26

Digital Output Subsystem Signals..............................................................................26

Counter/Timer Subsystem Signals.............................................................................27

Device Modes............................................................................................................28

Device Operations .....................................................................................................28

Digital Input Modes...................................................................................................29

Digital Input Operations............................................................................................29

Digital Input Timing Events ......................................................................................29

Digital Input Start Events...........................................................................................33

Digital Input Stop Events...........................................................................................35

Digital Input Channels...............................................................................................36

Digital Input Buffers..................................................................................................40

Digital Input Messages..............................................................................................40

Digital Output Modes................................................................................................42

Digital Output Operations..........................................................................................42

Digital Output Timing Events ....................................................................................42

Keithley KPCMCIA-PIO24 Series Contents • 3

Digital Output Start Events........................................................................................46

Digital Output Stop Events........................................................................................48

Digital Output Channels.............................................................................................49

Digital Output Buffers...............................................................................................53

Digital Output Messages............................................................................................53

Counter/Timer Subsystem........................................................................................................55

Uninstalling DriverLINX 57

How do I uninstall DriverLINX? .............................................................................................57

Troubleshooting 62

Solving Problems.....................................................................................................................62

Solving Problems Installing Drivers..........................................................................62

Solving Problems Configuring the Drivers................................................................62

Solving Problems Loading Drivers............................................................................63

Generating a DriverLINX Configuration Report......................................................................66

What is in the Report?................................................................................................66

How do I Generate the Report?..................................................................................66

Glossary of Terms 67

4 • Contents Keithley KPCMCIA-PIO24 Series

Preface

Software License and Software Disclaimer of Warranty

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Licensing Agreement

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Keithley KPCMCIA-PIO24 Series Preface • 5

Limited Warranty

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6 • Preface Keithley KPCMCIA-PIO24 Series

About DriverLINX

Welcome to DriverLINX for Microsoft Windows, the high-performance realtime data-acquisition device drivers for Windows application development.

DriverLINX is a language- and hardware-indepe ndent applic ation programming interface designed to support hardware manufacturers’ high-speed analog, digital,

and counter/timer data-acquisition boards in Windows. DriverLINX is a multi-user and multitasking data-acquisition resource manager providing more than 100 services for foreground and background data acquisition tasks.

Included with your DriverLINX package are the following items:

• The DriverLINX API DLLs and drivers supporting your data-

acquisition hardware

• Learn DriverLINX, an interactive learning and demonstration program

for DriverLINX that includes a Digital Storage Oscilloscope

• Source code for the sample programs

• The DriverLINX Application Programming Interface files for your

compiler

• DriverLINX On-line Help System

• DriverLINX Analog I/O Programming Guide

• DriverLINX Technical Reference Manual

• Supplemental Documentation on DriverLINX and your data acquisition

hardware

About This User’s Guide

The purpose of this manual is to help you quickly learn how to configure and use t he

hardware features of Keithley’s KPCMCIA-PIO24 card with DriverLINX.

• For more information on the DriverLINX API, please see the

DriverLINX Technical Reference Manual.

• For additional help programming your board, please examine the source

code examples on the Distribution Disks.

This manual contains the following chapters: Configuring the KPCMCIA-PIO24 Shows how to configure the KPCMCIA-PIO24 using the Configure DriverLINX

Device dialog box. Using the KPCMCIA-PIO24 with DriverLINX Shows how to set up DriverLINX with the Edit Service Request dialog box to use

KPCMCIA-PIO24 hardware features.

Keithley KPCMCIA-PIO24 Series Preface • 7

Conventions Used in This Manual

The following notational conventions are used in this manual:

• Itemized lists are identified by a round bullet (•).

• Numbered lists indicate a step-by-step procedure.

• DriverLINX Application Programming Interface and Windows macro

and function names are set in bold when mentioned in the text.

• DriverLINX indicates the exported function name of the device driver

DLL while DriverLINX indicates the product as a whole.

• DriverLINX Application Programming Interface identifiers, menu

items, and Dialog Box names are italicized when mentioned in the text.

• Italics are used for emphasis.

• Source code and data structure examples are displayed in Courier

typeface and bounded by a box with a single line.

Code

• Tables of information are bounded by a box with a double line.

Tables

Concept

• Important concepts and notes are printed in the left margin.

8 • Preface Keithley KPCMCIA-PIO24 Series

Configuring the KPCMCIA-PIO24

Introduction

This manual explains the steps and special features that apply to Keithley’s KPCMCIA-PIO24 card.

Installing and configuring DriverLINX for the Keithley KPCMCIA-PIO24 card requires three steps:

1. To install your KPCMCIA-PIO24 hardware, read and follow the

instructions in the hardware manual.

2. To install DriverLINX, follow the general procedure outlined in the

"Read Me First" material on the installation CD.

3. To configure DriverLINX, use the DriverLINX Configuration Panel.

Also see “Configure DriverLINX Device Dialog” on page 9 for configuration options specific to a Keithley KPCMCIA-PIO24 model.

Configure DriverLINX Device Dialog

DriverLINX uses a standardized configuration protocol for all data-acquisition hardware. Even though Windows 95/98/Me automatically selects the hardware base address and interrupt channel for the KPCMCIA-PIO24, you must still follow the configuration process to assign a DriverLINX Logical Device number to a specific KPCMCIA-PIO24 model in your computer.

When you activate the S

DriverLINX displays the Configure DriverLINX Device dialog. The following sections describe your choices for configuring DriverLINX to work with a Keithley KPCMCIA-PIO24 model.

Keithley KPCMCIA-PIO24 Series Configuring the KPCMCIA-PIO24 • 9

etup… button in the DriverLINX Configuration Panel,

10 • Configuring the KPCMCIA-PIO24 Keithley KPCMCIA-PIO24 Series

Device Subsystem Page

Note: The Configure DriverLINX Device dialog appears differently under different versions of Windows.

Use the Device subsystem page to tell DriverLINX the model name and address of your KPCMCIA-PIO24 card.

Vendor

The Vendor property displays “Keithley Instruments, Inc.” It is a read-only property.

Device

Windows 95/98/Me/2000

Windows NT

The Device property designates the Logical Device you are configuring. It is a readonly property. To change it, first save (OK) or quit (Cancel) the current configuration. Then select or create a new Logical Device using the DriverLINX Configuration Panel.

Model

The Model property selects the hardware model of the card you’re configuring. This driver supports only model KPCMCIA-PIO24.

Address

Windows 95/98/Me/2000 automatically selects an appropriate address and ignores this property.

The A

ddress property selects the I/O port address for the card. The default address used by DriverLINX is 768 decimal or 0x300 hex. If you have another peripheral card at the same address, you will have to select a free range of 8 addresses.

Detect

The Detect property enables and disables DriverLINX’s hardware detection and testing algorithms. For maximum system reliability, always leave this check box marked.

Keithley KPCMCIA-PIO24 Series Configuring the KPCMCIA-PIO24 • 11

Calibrate

The Calibrate property enables and disables hardware auto-calibration. For best accuracy, always leave this check box marked.

Special…

The Special… button displays a dialog for configuring any special, hardware-specific settings. For the KPCMCIA-PIO24 , Logical Device c onfiguration doe s not require any special settings so DriverLINX disables the S

pecial… button.

12 • Configuring the KPCMCIA-PIO24 Keithley KPCMCIA-PIO24 Series

Digital Input Subsystem Page

Channels

The Channels property allows you to select a Logical Channel for configuration or viewing the channel’s range. Only the KPCMCIA-PIO24 digital input/output

channels support programmable configuration. DriverLINX defines the following Logical Channels for the KPCMCIA-PIO24

digital inputs:

Windows 95/98/Me/2000

Windows NT

Logical Channel DriverLINX Function KPCMCIA-PIO24 External

Connector

0 Digital Input/Output Port Digital input/output lines

PA0 - PA7

1 Digital Input/Output Port Digital input/output lines

PB0 - PB7

2 Digital Input/Output Port Digital input/output lines

PC0 - PC7

3 External Clock INTERRUPT INPUT

Range

The Range property specifies the supported digital input range for the selected Logical Channel. This is a read-only property.

Interrupt

For Windows 95/98/Me/2000, the operating system automatically determines the interrupt channel for the KPCMCIA-PIO24 card. DriverLINX disables this property.

For Windows NT, select a free interrupt request level to support interrupt mode transfers. Valid IRQ levels are: 1 - 15.

DMA level

The KPCMCIA-PIO24 does not use system DMA channels. DriverLINX disables this property and displays it as blank.

Keithley KPCMCIA-PIO24 Series Configuring the KPCMCIA-PIO24 • 13

Use caution when configuring and connecting lines to the digital I/O ports. Connecting an input line to an output port, or vice versa, could damage the hardware.

Configuration Setup

The Configuration S I/O ports. The KPCMCIA-PIO24 allows configuring each line of the 8-bit I/O ports for either input or output.

DriverLINX supports two methods for configuring a digital I/O port. The simplified method configures the whole port, while the advanced method allows you to configure groups of digital I/O lines. Select the channel to configure in the dropdown channel list and enter a S

etup property specifies the hardware configuration of the digital

etup value using one of the methods below.

Simplified Digital I/O Port Configuration

For simplified configuration:

1. Select the channel number of the port to configure in the drop-down channel list.

2. Check the Initialize box.

3. Enter one of the following values for the S the entire port:

• 1—configures all lines in the port as input, or

• 0—configures all lines in the port as output.

Advanced Digital I/O Port Configuration

With advanced configuration, you can divide the port into groups of 1, 2, 4 or 8 lines and configure each group separately.

For advanced configuration:

1. Select the channel number of the port to configure in the drop-down channel list.

2. Check the Initialize box.

3. Enter a value for the S

etup property as described below.

etup property to configure

The following table describes each grouping. Choose whichever grouping is most convenient.

Grouping Number of Lines in

Each Group

Byte 8 1 Nibble 4 2 Half-Nibble 2 4 Bit 1 8

For advanced configuration, t he S components:

14 • Configuring the KPCMCIA-PIO24 Keithley KPCMCIA-PIO24 Series

etup property value has two variable-sized

Number of Groups in the Port

• Direction Field—consists of a bit for each group in the port. Each bit

indicates the input/output direction of the lines in the group. The leastsignificant bit configures the first group. High-order bits to the left configure subsequent groups.

For each bit, enter one of the following values to configure the group:

• 1—configures all lines in the group as input, or

• 0—configures all lines in the group as output.

• Group Size Field—consists of a binary 1 immediately to the left of

the Direction field. This allows the position of the S

etup property’s

leftmost 1 to indicate the start of the Direction field.

The following diagrams show the format of the S

etup property for each grouping. All formats have the Group Size field in the high-order bits and the Direction field in the low-order bits.

Byte-Sized Groups



06%

• Direction Field—has one bit to configure the single byte-sized group

• Group Size Field—has a value of 0x2 (hexadecimal) or 2 (decimal)

Nibble-Sized Groups

/6%



06%

• Direction Field—has two bits to configure the two nibble-sized

groups

• Group Size Field—has a value of 0x4 (hexadecimal) or 4 (decimal)

Half Nibble-Sized Groups

/6%



06%

• Direction Field—has four bits to configure the fo ur half nibble-sized

groups

• Group Size Field—has a value of 0x10 (hexadecimal) or 16

(decimal)

Bit-Sized Groups

/6%



06%

• Direction Field—has eight bits to configure the eight bit-sized groups

Keithley KPCMCIA-PIO24 Series Configuring the KPCMCIA-PIO24 • 15

/6%

• Group Size Field—has a value of 0x100 (hexadecimal) or

512 (decimal)

Advanced Configuration Example: This example shows how to configure the port in nibbles. It configures the first

nibble as output and the second as input.

1. Choose the Nibble-Sized format and fill in the Direction field, right-toleft, as follows:

0—to configure the first nibble as output 1—to configure the second nibble as input







06%

2. Calculate the hexadecimal or decimal value:

0x4 + 0x2 + 0x0 = 0x6 4 + 2 + 0 = 6

3. Then, enter 0x6 (hexadecimal) or 6 (decimal) for the Setup property.

/6%

Initialize

Checking the Initialize check box instructs DriverLINX to use the Configuration S

etup property to configure the digital I/O ports. Check Initialize to put the

configuration setup into effect.

Dec

This check box converts the Configuration Setup property to decimal.

Hex

This check box converts the Configuration Setup property to hexadecimal.

16 • Configuring the KPCMCIA-PIO24 Keithley KPCMCIA-PIO24 Series

Digital Output Subsystem Page

Use the Digital Output subsystem page to change the default digital output port initialization values.

Channels

The Channels property allows you to select a Logical Channel for initialization or

viewing the channel’s range. KPCMCIA-PIO24 card has three digital input/output ports. The Digital Output subsystem shares these ports with the Digital Input subsystem. The KPCMCIA-PIO24 requires configuration of each line in the digital input/output ports as input or output. See “Digital Input Subsystem Page” on page 13.

Range

The Range property specifies the supported digital output range for the selected Logical Channel. This is a read-only property.

Interrupt

The KPCMCIA-PIO24 uses the same interrupt for digital output as for digital input. Go to the Digital Input page to set it. DriverLINX disables this property and displays it as blank.

DMA level

The KPCMCIA-PIO24 does not use system DMA channels. DriverLINX disables this property and displays it as blank.

Initialization Value

The Initialization Value property specifies the digital output value DriverLINX will write to the selected Logical Channel on hardware initialization. DriverLINX only writes this value if you enable the In the hardware-defined initialization values if the In For the KPCMCIA-PIO24, the default digital output value is zero.

itialize check box. By default, DriverLINX uses

itialize check box is not checked.

Initialize

Checking the Initialize check box instructs DriverLINX to use the Initialization V

alue property, rather than the default value, for digital output port initialization.

Keithley KPCMCIA-PIO24 Series Configuring the KPCMCIA-PIO24 • 17

Dec

This check box converts the Initialization Value property to decimal.

Hex

This check box converts the Initialization Value property to hexadecimal.

18 • Configuring the KPCMCIA-PIO24 Keithley KPCMCIA-PIO24 Series

For the KPCMCIA-PIO24, there are no configurable options on the Counter/Timer subsystem page.

Counter/Timer Subsystem Page

Resolution

The Resolution property specifies the clock frequency of the master oscillator. DriverLINX provides a System Pacer Clock which simulates a 1 MHz hardware clock for pacing input/output tasks.

Interrupt

The KPCMCIA-PIO24 does not support interrupts from counter/timers. DriverLINX disables this property and displays it as blank.

Keithley KPCMCIA-PIO24 Series Configuring the KPCMCIA-PIO24 • 19

Using the KPCMCIA-PIO24 with DriverLINX

Introduction

This chapter shows you how to set up and use KPCMCIA-PIO24 hardware features with DriverLINX. The descriptions here use the Edit Service Request dialogs for

language and API i ndependence. For the corre ct syntax with the language you’re using, please see the DriverLINX Technical Reference Manuals. For DriverLINX examples in your programming language, please see the source code examples in the subdirectories of your DriverLINX installation directory or on the original Distribution Media.

DriverLINX Hardware Model for KPCMCIA-PIO24

By design, DriverLINX provides a portable, hardware-independent API for dataacquisition boards while still allowing applications to access unique or proprietary hardware features of specific products. To achieve this goal, DriverLINX maps a hardware-independent, or abstract, data-acquisition model onto KPCMCIA-PIO24 hardware capabilities.

The following sections describe how DriverLINX implements KPCMCIA-PIO24 hardware features as Subsystems, Modes, Operations, Events, Logical Channels, Buffers, and Messages.

DriverLINX Subsystems

The KPCMCIA-PIO24 supports four of DriverLINX’s six Logical Subsystems:

1. Device—refers to the KPCMCIA-PIO24 card as a whole.

2. Analog Input—refers to the analog input channels, clocks, and control

signals. The KPCMCIA-PIO24 does not support analog input.

3. Analog Output—refers to the analog output channels, clocks, and

control signals. The KPCMCIA-PIO24 does not support analog output.

4. Digital Input—refers to the 8-bit digital input/output ports as well as

the 1-bit digital input (TTL) control signals, INTERRUPT INPUT.

Keithley KPCMCIA-PIO24 Series Using the KPCMCIA-PIO24 with DriverLINX • 21

5. Digital Output—refers to the 8-bit digital input/output ports.

6. Counter/Timer—refers to the clock channel for pacing input/output tasks.

DriverLINX Modes

Applications use modes in Service Requests to advise DriverLINX on their preferred hardware data transfer technique. The DriverLINX modes fall into two general classes:

• Foreground or synchronous modes. The calling application doesn’t regain control until DriverLINX completes the Service Request. DriverLINX supports this mode for simple, single value I/O operations or software housekeeping functions that DriverLINX can complete without a significant delay.

• Background or asynchronous modes. The calling application regains control as soon as DriverLINX initiates the task. The calling application must synchronize with the data-acquisition task using status polling or DriverLINX’s messages (preferred). DriverLINX supports this mode for buffered data transfers or for commands that require a significant time to complete.

DriverLINX supports three of the four modes with the KPCMCIA-PIO24 for its commands (Service Requests).

• Polled Mode—This is a foreground or synchronous op eration. DriverLINX supports this mode for simple, single-value I/O operations that the data-acquisition card can complete without significant delay.

• Interrupt Mode—T his is a background or asynchronous op eration. DriverLINX transfers data between the computer’s memory and the data-acquisition card using hardware interrupts and programmed I/O transfers.

• DMA Mode—This is a backgro und or asynchronous o peration. DriverLINX transfers data between the computer’s memory and the data-acquisition card using memory bus transfers. The KPCMCIA- PIO24 does not support this transfer mode.

• Other Mode—This i s a foreground or synchronous operation. DriverLINX supports this mode for initialization, configuration, calibration, data conversion, and timebase operations.

The following table summarizes the data acquisition modes that DriverLINX supports for each subsystem with the Keithley KPCMCIA-PIO24.

22 • Using the KPCMCIA-PIO24 with DriverLINX Keithley KPCMCIA-PIO24 Series

Subsystem Polled Interrupt DMA Other

Analog Input Analog Output Digital Input Digital Output Counter/Timer Device

√ √ √ √

KPCMCIA-PIO24 Supported DriverLINX Modes

√ √ √ √

DriverLINX Operations and Events

Applications construct DriverLINX data-acquisition tasks by combining a small number of DriverLINX operations and events in many possible ways. The following table summarizes the operations and events that DriverLINX supports for the Keithley KPCMCIA-PIO24. Latter sections for each DriverLINX subsystem will describe the operations and events in more detail.

Keithley KPCMCIA-PIO24 Series Using the KPCMCIA-PIO24 with DriverLINX • 23

Note: All subsystems allow the MESSAGE operation, which is not shown in the

table. DriverLINX allows any Mode setting for the MESSAGE operation.

Subsystem Operation Events

Mode Timing Start Stop

Analog Input

Analog Output

Digital Input

Polled Start null null, cmd null, TC

Interrupt Start, Stop, Status dig, rate cmd, dig cmd, TC, dig

Other Initialize

Digital Output

Polled Start null null, cmd null, TC

Interrupt Start, Stop, Status dig, rate cmd, dig cmd, TC, dig

Other Initialize

Counter/Timer

Other Initialize

Device

Other Initialize,

Configure, Capabilities

Allowed Operations and Events for KPCMCIA-PIO24 Subsystems and Modes

The following list explains the Event abbreviations in the preceding table:

• null—Null or None Event when a Service Request doesn’t require an event

• cmd—Command Event when DriverLINX starts or stops a task on software command

• TC—Terminal Count Event when DriverLINX processes all data buffers once

24 • Using the KPCMCIA-PIO24 with DriverLINX Keithley KPCMCIA-PIO24 Series

• rate—Rate Event specifies how DriverLINX paces or clocks data

transfer

• dig—Digital Event specifies a trigger, clock, or other control signal to

pace, start, or stop a task

Logical Channels

DriverLINX designates the individually addressable hardware channels for each subsystem as “Logical Channels”. Generally, the zero-based Logical Channel numbering sequence c losely follows the hardware channel numbering scheme.

In some cases, however, DriverLINX assigns Logical Channel numbers to hardware features that users don’t commonly think of as “channels”. For instance, DriverLINX commonly models external hardware clock input lines, external hardware trigger input lines, and external interrupt inputs as 1-bit digital Logical Channels. In other cases, DriverLINX models subsystem-specific features, such as internal pacer clocks, as members of a more general purpose set of counter/timer channels.

For how DriverLINX assigns Logical Channel numbers, see the notes for each supported subsystem.

Buffers

Applications usually use data buffers to exchange data between the application and the data-acquisition hardware. When using data buffers, please observe the following points about DriverLINX’s data buffers:

• DriverLINX supports data-acquisition tasks with 1 to 255 data buffers

per task.

• DriverLINX imposes no size limits on a single buffer, although the

operating system or some hardware products may have size restrictions.

• User applications must allow DriverLINX to allocate all data buffers to

guarantee application portability to different hardware and operating systems and to insure that the hardware can physically access the buffer memory.

• User applications usually don’t have concurrent or immediate access to

the in-use data buffer while DriverLINX is executing a data-acquisition task.

Keithley KPCMCIA-PIO24 Series Using the KPCMCIA-PIO24 with DriverLINX • 25

Connecting Signals to the KPCMCIA-PIO24

The Keithley hardware manual describes the data and control signals for the KPCMCIA-PIO24 and the connector pinouts for these signals. This section summarizes how DriverLINX logically numbers the I/O data signals and how DriverLINX uses several of these control signals for external clock and trigger inputs.

Digital Input Subsystem Signals

The Digital Input subsystem has three 8-bit digital input/output ports and one control input which DriverLINX models as a 1-bit logical digital input port. DriverLINX maps these signals to Logical Channels as shown in the following table:

Port Connector Name Logical Channels

Digital Input/Output Port A PA0 – PA7 0 Digital Input/Output Port B PB0 – PB7 1 Digital Input/Output Port C PC0 – PC7 2 External clock alias INTERRUPT INPUT 3

How DriverLINX maps digital input hardware channels to Logical Channels

Note: To use a line in an 8-bit digital input/output port for input, first configure it for input on the Digital Input Subsystem Page of the DriverLINX Configuration Panel.

See “Configuring the KPCMCIA-PIO24” on page 9. The Digital Input subsystem shares the System Pacer Clock with the Digital Output

subsystem. DriverLINX designates the System Pacer Clock as Logical Channel 0 of the Counter/Timer subsystem.

Digital Output Subsystem Signals

The Digital Output subsystem has three 8-bit digital input/output ports. DriverLINX maps these signals to Logical Channels as shown in the following table:

Port Connector Name Logical Channels

Digital Input/Output Port A PA0 – PA7 0 Digital Input/Output Port B PB0 – PB7 1 Digital Input/Output Port C PC0 – PC7 2

How DriverLINX maps digital output hardware channels to Logical Channels

Note: To use a line in an 8-bit digital input/output port for output, first configure it for output on the Digital Input Subsystem Page of the DriverLINX Configuration

Panel. See “Configuring the KPCMCIA-PIO24” on page 9. The Digital Output subsystem shares the System Pacer Clock with the Digital Input

subsystem. DriverLINX designates the System Pacer Clock as Logical Channel 0 of the Counter/Timer subsystem.

26 • Using the KPCMCIA-PIO24 with DriverLINX Keithley KPCMCIA-PIO24 Series

Counter/Timer Subsystem Signals

DriverLINX provides a system timer using software to pace digital input/output. DriverLINX maps the timer to Logical Channel 0.

Timer Connector Name Logical Channels

System timer none 0

How DriverLINX maps counter/timer hardware channels to Logical Channels

Applications can’t use this timer independently from tasks on an input/output subsystem.

Keithley KPCMCIA-PIO24 Series Using the KPCMCIA-PIO24 with DriverLINX • 27

Device Subsystem

The following sections describe how DriverLINX implements Device Subsystem features for the KPCMCIA-PIO24.

Device Modes

The Device Subsystem only supports DriverLINX’s Other mode for all operations.

Device Operations

The KPCMCIA-PIO24 Device Subsystem supports the following DriverLINX operations:

If another process is using the same data-acquisition card, DriverLINX will prevent Device Initialization from interfering with another process’s data-acquisition tasks.

• Initialize—DriverLINX aborts all data-acquisition tasks for every subsystem controlled by the current process. DriverLINX then performs an initialization for each supported subsystem.

• Configure—DriverLINX displays the Configure DriverLINX Device dialog for the current Logical Device. Please use the DriverLINX Configuration Panel rather than this operation to configure DriverLINX.

• Capabilities—DriverLINX provides hardware-specific and configuration information in the form of a Logical Device Descriptor database.

28 • Using the KPCMCIA-PIO24 with DriverLINX Keithley KPCMCIA-PIO24 Series

Digital Input Subsystem

The following sections describe how DriverLINX implements Digital Input Subsystem features for the KPCMCIA-PIO24.

Digital Input Modes

The Digital Input Subsystem supports the following modes:

• Polled—For single value digital input samples.

• Interrupt—For buffered transfers using programmed I/O.

• Other—For subsystem initialization and data conversion.

Digital Input Operations

The KPCMCIA-PIO24 Digital Input Subsystem supports the following DriverLINX operations:

• Initialize—aborts any active interrupt data-acquisition tasks and stops

the clock. DriverLINX prevents one application process from interfering with another process’s data-acquisition tasks.

• Start—initiates a data-acquisition task using the Mode, Timing, Start,

and Stop Events, the Logical Channels, and the Buffers the application specified in the Service Request.

• Status—reports the buffer position of the next sample that DriverLINX

will read into a buffer.

• Stop—terminates a digital input data-acquisition task.

• Message—DriverLINX displays a pop-up dialog box for the user

containing the text for the current DriverLINX error message.

Digital Port Configuration

The KPCMCIA-PIO24 has three shared digital input/output ports that require configuration before connecting signals. Therefore, DriverLINX does not allow the application to configure the KPCMCIA-PIO24’s digital I/O ports.

Note: To use a line in an 8-bit digital input/output port for input, first configure it for input on the Digital Input Subsystem Page of the DriverLINX Configuration Panel. See “Configuring the KPCMCIA-PIO24” on page 9.

Digital Input Timing Events

Timing Events specify how the hardware paces or clocks the reading of Digital Input samples. DriverLINX uses the Timing Event to program when the KPCMCIA-PIO24 reads the next digital input sample from the port.

Keithley KPCMCIA-PIO24 Series Using the KPCMCIA-PIO24 with DriverLINX • 29

The KPCMCIA-PIO24 supports the following Timing Events:

• None—Input requires no pacing as DriverLINX is reading only a single value.

• Rate—The KPCMCIA-PIO24 supports only fixed rate digital input using internal and external clocks.

• Digital—DriverLINX uses an external digital input signal to pace the acquisition of each sample.

None or Null Event

The Null Event specifies that the task does not need a clock to determine when to read the next sample.

Rate Event

The KPCMCIA-PIO24 supports one type of Rate Event for digital input:

• Rate Generator—Generates a fixed rate clock with equal time intervals between tics.

Rate Generator: Internal Clocking

An internally clocked Rate Generator produces a fixed rate clock with equal time intervals between tics.

Period

As the KPCMCIA-PIO24 doesn’t support a dedicated clock for digital input timing, DriverLINX uses the operating system timing clock for pacing digital input. The system timing clock doesn’t have the resolution or time granularity of a dedicated clock, but it is an excellent substitute for low frequency digital input polling operations.

30 • Using the KPCMCIA-PIO24 with DriverLINX Keithley KPCMCIA-PIO24 Series

How to set up the KPCMCIA-PIO24 for fixed rate sampling using an internal clock.

For hardware independence, specify the clock channel using the symbolic constant, DEFAULTTIMER, which always maps to the default Logical Channel for digital input timing.

• Specify internal clocking using a Rate Generator on Logical

Channel 0 with the Internal 1 Clock source.

• The Period property specifies the time interval between samples in tics,

where a system timer tic is 1 µs, or 1 MHz. The minimum period is 1000 tics, or 1 kHz. The maximum period is 4,294,967,295 tics

(

1232− ), or 0.0002 Hz. The resolution and granularity of the system

timer are operating system dependent. Under current versions of Windows, throughput is less than 1 kHz. See “Counter/Timer Subsystem” on page 55 for details on the system timer.

Rate Generator: External Clocki ng

An externally clocke d Rate Generator produces a rate clock with unknown time intervals between tics.

Period (ext clk)

Use an externally clocked rate generator when you want to synchronize digital input samples with a recurrent external signal.

Keithley KPCMCIA-PIO24 Series Using the KPCMCIA-PIO24 with DriverLINX • 31

How to set up the KPCMCIA-PIO24 for fixed rate sampling using an external clock.

A task cannot use the INTERRUPT INPUT line (Digital Input Logical Channel 3) for a digital start or stop event while using it as an external clock source.

BE SURE that the external clock source is TTL compatible, 0 V minimum to +5 V maximum!

• Specify external clocking using a Rate Generator on Logical Channel 0 with an External, External+ or External– Clock source. External

and External+ both specify sampling on the rising, or positive, edge of the external clock signal. External– specifies sampling on the falling, or negative, edge of the external clock signal.

• Users should connect the external clock signal to the INTERRUPT INPUT line.

• The Period may be any value ≥ 20 tics, or 20 µs. The period value

doesn’t affect the external clock frequency, but DriverLINX requires a valid hardware value in case the application requests a timebase operation and to optimize data transfer between the driver and the application.

Digital Event

DriverLINX supports Digital Events as aliases for externally clocked Rate Generators. Use this technique for compatibility with data-acquisition products that only support externally clock sources.

32 • Using the KPCMCIA-PIO24 with DriverLINX Keithley KPCMCIA-PIO24 Series

How to set up the KPCMCIA-P I O24 for external rate samp ling using a digital event.

Digital Timing Events contain mask, pattern, and match fields. The mask is logically AND with the digital input data on the Logical Channel and then compared against the pattern for a match/mismatch.

A task cannot use a channel

or a digital start or stop event while using it for a digital timing event.

BE SURE that the external clock source is TTL compatible, 0 V minimum to +5 V maximum!

• Specify external clocking using Logical Channel 2 or 3. For hardware-

independence, you can specify the hardware external trigger channel by the symbolic constant, DI_EXTCLK.

• Users should connect the external clock signal to an input line in port

C ( PC0 - PC7) for channel 2 or the INTERRUPT INPUT line for channel 3.

• Specify the Mask property with a single bit set to indicate that

DriverLINX should only compare a 1-bit digital input value against the Pattern property.

• Specify the Match property as N

• Specify the Pattern property as 0 for a rising, or positive, edge clock

(≠1), or with the same bit set as in the mask for a falling, or negativ e, edge clock (≠0).

ot Equals.

Digital Input Start Events

Start Events specify when the KPCMCIA-PIO24 hardware starts reading digital input data.

The KPCMCIA-PIO24 supports the following Start Events for digital input:

• None—Use this event when the DriverLINX operation doesn’t require

a Start Event.

Keithley KPCMCIA-PIO24 Series Using the KPCMCIA-PIO24 with DriverLINX • 33

• Command—DriverLINX starts the task on software command, i.e., as

soon as DriverLINX finishes programming the KPCMCIA-PIO24 hardware for the task.

• Digital—The KPCMCIA-PIO24 starts acquiring digital input samples

when the hardware detects the digital Logical Channel input satisfies the digital condition specified in the Start Event.

None or Null Event

The Null Event specifies that the task does not need a Start Event to begin the task.

Command Event

The Command Event starts data acquisition as soon as DriverLINX has completed programming the KPCMCIA-PIO24 hardware with the task parameters.

Digital Event or Post-Triggering

The KPCMCIA-PIO24 can acquire digital input samples after the hardware detects a digital trigger condition. Use post-triggering when you want to synchronize the start of data acquisition with an external signal.

How to set up the KPCMCIA-PIO24 for post-triggered digital input.

A Digital Start Event requires an external timing source because the KPCMCIA-PIO24 does not have a hardware clock.

A task cannot use a channel

or a digital start or stop event while using it for a digital timing event.

34 • Using the KPCMCIA-PIO24 with DriverLINX Keithley KPCMCIA-PIO24 Series

Digital Start Events contain mask, pattern, and match fields. The mask is logically AND with the digital input data on the Logical Channel and then compared against the pattern for a match/mismatch.

• Specify the Logical Channel as 0, 1, 2 or 3.

• Specify the Mask property to indicate that DriverLINX should only

compare selected bits in the digital input value against the Pattern property.

• Specify the Match property as Equals to trigger on an exact match of

the digital pattern to the masked digital input. Match on Not Equals triggers on any difference between the masked digital input and the Pattern.

• Specify the Pattern property to compare with the masked digital input

value.

• Specify the Delay property as any number of samples from 0 to

1232− .

Digital Input Stop Events

Stop Events specify when the KPCMCIA-PIO24 hardware stops reading digital input data.

The KPCMCIA-PIO24 supports the following Stop Events for digital input:

• None—Use this event when the DriverLINX operation doesn’t require

a Stop Event.

• Command—DriverLINX stops the task on software command, i.e.,

when the application issues a Service Request with a Stop operation.

• Terminal count—DriverLINX stops the task after the

KPCMCIA-PIO24 hardware has filled all the data buffers once.

• Digital—The KPCMCIA-PIO24 stops the task when the hardware

detects the digital Logical Channel input satisfies the digital condition specified in the Stop Event.

None or Null Event

The Null Event specifies that the task does not need a Stop Event to end the task.

Command Event

The Command Event stops data acquisition when the user application changes the Operation property in the Service Request to Stop and resubmits the Service Request to DriverLINX.

In stop-on-command mode, DriverLINX continuously cycles through all the data buffers, reading from the digital ports on the KPCMCIA-PIO24.

Terminal Count Event

The Terminal Count Event stops data acquisition after DriverLINX has read the digital input data into all the data buffers once. Use terminal count when you want to read a fixed amount of data.

Digital Event or Pre-Triggering

The KPCMCIA-PIO24 can acquire digital input samples until the hardware detects a digital trigger condition. Use pre-triggering when you want to synchronize the end of data acquisition with an external signal.

Keithley KPCMCIA-PIO24 Series Using the KPCMCIA-PIO24 with DriverLINX • 35

How to set up the KPCMCIA-PIO24 for pre-triggered digital input.

A Digital Start Event requires an external timing source because the KPCMCIA-PIO24 does not have a hardware clock.

A task cannot use a channel

or a digital start or stop event while using it for a digital timing event.

Digital Start Events contain mask, pattern, and match fields. The mask is logically AND with the digital input data on the Logical Channel and then compared against the pattern for a match/mismatch.

• Specify the Logical Channel as 0, 1, 2 or 3.

• Specify the Mask property to indicate that DriverLINX should only

compare selected bits in the digital input value against the Pattern property.

• Specify the Match property as Equals to trigger on an exact match of

the digital pattern to the masked digital input. Match on Not Equals triggers on any difference between the masked digital input and the Pattern.

• Specify the Pattern property to compare with the masked digital input

value.

• Specify the Delay property as any number of samples from 0 to

1232− .

Digital Input Channels

The KPCMCIA-PIO24 allows applications to specify the digital channels using three techniques:

• Start Channel—Acquire data from a single channel.

• Start/Stop Channel Range—Acquire data from a consecutive range of

channels.

• Channel List—Acquire digital data a list of channels.

36 • Using the KPCMCIA-PIO24 with DriverLINX Keithley KPCMCIA-PIO24 Series

Digital Input Logical Channels

The KPCMCIA-PIO24 has three digital input/output ports that DriverLINX designates as Logical Channels 0 to 2. DriverLINX defines an additional Logical Channel for the external clock signal but applications cannot directly read its value.

Logical Channel DriverLINX Function KPCMCIA-PIO24 External

Connector

0 Digital Input/Output Port Digital input/output lines

PA0 - PA7

1 Digital Input/Output Port Digital input/output lines

PB0 - PB7

2 Digital Input/Output Port Digital input/output lines

PC0 - PC7

3 External Clock INTERRUPT INPUT

Extended Logical Channel Addressing

DriverLINX supports a software extension to Logical Channel addressing that allows applications to combine adjacent Logical Channels into a single channel or split a Logical Channel into smaller addressable parts. For instance, applications can address individual bits of a digital port or read and write multiple ports as a single value.

To use the Logical Channel addressing extensions, fo rm a 16-bit Logica l Channel address by combining the channel number of an addressable unit with a size field as follows:

6L]H&RGH



  

&KDQQHO1XPEHU

The following table specifies the 3-bit size codes:

Size Code Unit Bits

0 native varies with hardware 1 bit 1 2 half nibble 2 3 nibble 4 4 byte 8 5 word 16 6 dword 32 7 qword 64

"Native" units refer to the hardware-defined digital channel size. For most boards, this is the same as an 8-bit byte. When using extended Logical Channel addressing, DriverLINX groups digital bits in units defined by the size code and then assigns consecutive channel numbers starting from zero.

Keithley KPCMCIA-PIO24 Series Using the KPCMCIA-PIO24 with DriverLINX • 37

For the KPCMCIA-PIO24, the 8-bit digital input/output ports have the following channel addresses for each size code:

Unit Channels Address (dec) Address (hex)

native 0..2 0..2 0..2 bit 0..23 4096..4119 1000..1017 half nibble 0..11 8192..8203 2000..200B nibble 0..5 12288..12293 3000..3005 byte 0..2 16384..16386 4000..4002 word 0..0 20480..20480 5000..5000

Notes:

• DriverLINX supports only single-value transfers on Logical Channels

that are smaller than the native size.

• Word addressing accesses Ports A and B only.

Single Channel Digital Input

In this mode, the KPCMCIA-PIO24 acquires all data from one channel.

How to set up the KPCMCIA-PIO24 to read from a single channel

Multi-channel Digital Input Range

In this mode, the KPCMCIA-PIO24 acquires all data from a consecutive range of digital channels.

• For the KPCMCIA-PIO24, the Start Channel number must be less than

or equal to the Stop Channel number.

38 • Using the KPCMCIA-PIO24 with DriverLINX Keithley KPCMCIA-PIO24 Series

How to set up the KPCMCIA-PIO24 to read from a range of channels

Multi-channel Digital Input List

In this mode, the KPCMCIA-PIO24 acquires all data from a random list of digital channels.

• In simultaneous mode, the list cannot repeat any Logical Channel

numbers.

How to set up the KPCMCIA-PIO24 to read from a range of channels

Keithley KPCMCIA-PIO24 Series Using the KPCMCIA-PIO24 with DriverLINX • 39

Digital Input Buffers

DriverLINX supports both single-value digital input and buffered digital input.

• For single-value output, specify the Number of buffers as 0 and the

buffer size as 0.

• For buffered output, specify the Number of buffers from 1 to 256 and

the buffer size as desired.

How to set up the KPCMCIA-PIO24 to read digital samples using data buffers

An individual DriverLINX buffer may have any size as long as the buffer length holds an integral number of channel scans, i.e., the number of digital input channels

you’re acquiring. This restriction enforces the requirement that all input channels have the same number of samples.

Digital Input Messages

For digital input operations, DriverLINX can report the following messages to the application:

DriverLINX Message Explanation

Service Start DriverLINX has started the acquisition task. Service Done DriverLINX has completed the acquisition task. Buffer Filled DriverLINX has filled a data buffer with digital input Start Event DriverLINX has processed the interrupt for a hardware start

event

Stop Event DriverLINX has processed the interrupt for a hardware stop

event

Data Lost DriverLINX has detected a digital input data overrun

condition.

Critical Error DriverLINX has encountered an unexpected hardware or

40 • Using the KPCMCIA-PIO24 with DriverLINX Keithley KPCMCIA-PIO24 Series

software condition.

DriverLINX Event message for digital input

Keithley KPCMCIA-PIO24 Series Using the KPCMCIA-PIO24 with DriverLINX • 41

Digital Output Subsystem

The following sections describe how DriverLINX implements Digital Output Subsystem features for the KPCMCIA-PIO24.

Digital Output Modes

The Digital Output Subsystem supports the following modes:

• Polled—For single value digital output samples.

• Interrupt—For buffered transfers using programmed I/O.

• Other—For subsystem initialization and data conversion.

Digital Output Operations

The KPCMCIA-PIO24 Digital Output Subsystem supports the following DriverLINX operations:

• Initialize—aborts any active interrupt data-acquisition tasks and stops

the clock. DriverLINX prevents one application process from interfering with another process’s data-acquisition tasks.

• Start—initiates a data-acquisition task using the Mode, Timing, Start,

and Stop Events, the Logical Channels, and the Buffers the application specified in the Service Request.

• Status—reports the buffer position of the next sample that DriverLINX

will write from a buffer.

• Stop—terminates an digital output data-acquisition task.

• Message—DriverLINX displays a pop-up dialog box for the user

containing the text for the current DriverLINX error message.

Digital Port Configuration

Note: To use a line in an 8-bit digital input/output port for output, first configure it for output on the Digital Input Subsystem Page of the DriverLINX Configuration Panel. See “Configuring the KPCMCIA-PIO24” on page 9.

Digital Output Initialization

By default, the Digital Output subsystem writes zero into the digital output ports. You can specify a different initial output value using the Configure DriverLINX Device dialog. See “Digital Output Subsystem Page” on page 17.

Digital Output Timing Events

Timing Events specify how the hardware paces or clocks writing Digital Output samples. DriverLINX uses the Timing Event to program when the KPCMCIA-PIO24 writes the next digital output sample to the ports.

42 • Using the KPCMCIA-PIO24 with DriverLINX Keithley KPCMCIA-PIO24 Series

The KPCMCIA-PIO24 supports the following Timing Events:

• None—Output requires no pacing as DriverLINX is writing only a

single value.

• Rate—The KPCMCIA-PIO24 supports only fixed rate digital output

using internal and external clocks.

• Digital—DriverLINX uses an external digital input signal to pace the

output of each sample.

None or Null Event

The Null Event specifies that the task does not need a clock to determine when to write the next sample.

Rate Event

The KPCMCIA-PIO24 supports one type of Rate Event for digital output:

• Rate Generator—Generates a fixed rate clock with equal time

intervals between tics.

Rate Generator: Internal Clocking

An internally clocked Rate Generator produces a fixed rate clock with equal time intervals between tics.

Period

Keithley KPCMCIA-PIO24 Series Using the KPCMCIA-PIO24 with DriverLINX • 43

As the KP CMCIA-PIO24 doesn’t support a dedicated clock for digital output timing, DriverLINX uses the operating system timing clock for pacing digital output. The system timing clock doesn’t have the resolution or time granularity of a dedicated clock, but it is an excellent substitute for low frequency digital output polling operations.

For hardware independence, specify the clock channel using the symbolic constant, DEFAULTTIMER, which always maps to the default Logical Channel for digital output timing.

How to set up the KPCMCIA-PIO24 for fixed rate sampling using an internal clock.

• Specify internal clocking using a Rate Generator on Logical

Channel 0 with the Internal 1 Clock source.

• The Period property specifies the time interval between samples in tics,

where a system timer tic is 1 µs, or 1 MHz. The minimum period is 1000 tics, or 1 kHz. The maximum period is 4,294,967,295 tics

(

1232− ), or 0.0002 Hz. The resolution and granularity of the system

timer are operating system dependent. Under current versions of Windows, throughput is less than 1 kHz. See “Counter/Timer Subsystem” on page 55 for details on the system timer.

Rate Generator: External Clocki ng

An externally clocke d Rate Generator produces a rate clock with unknown time intervals between tics.

Period (ext clk)

Use an externally clocked rate generator when you want to synchronize digital output samples with a recurrent external signal.

44 • Using the KPCMCIA-PIO24 with DriverLINX Keithley KPCMCIA-PIO24 Series

How to set up the KPCMCIA-PIO24 for fixed rate sampling using an external clock.

A task cannot use the INTERRUPT INPUT line (Digital Input Logical Channel 3) for a digital start or stop event while using it as an external clock source.

BE SURE that the external clock source is TTL compatible, 0 V minimum to +5 V maximum!

• Specify external clocking using a Rate Generator on Logical Channel

0 with an External, External+ or External– Clock source. External

and External+ both specify sampling on the rising, or positive, edge of the external clock signal. External– specifies sampling on the falling, or negative, edge of the external clock signal.

• Users should connect the external clock signal to the INTERRUPT

INPUT line.

• The Period may be any value ≥ 20 tics, or 20 µs. The period value

Digital Event

DriverLINX supports Digital Events as aliases for externally clocked Rate Generators. Use this technique for compatibility with data-acquisition products that only support externally clock sources.

Keithley KPCMCIA-PIO24 Series Using the KPCMCIA-PIO24 with DriverLINX • 45