Network Card User Manual
Table Of Contents
- SCXI-1121 User Manual
- Support
- Important Information
- Contents
- About This Manual
- Chapter 1 Introduction
- Chapter 2 Configuration and Installation
- Chapter 3 Theory of Operation
- Chapter 4 Register Descriptions
- Chapter 5 Programming
- Appendix A Specifications
- Appendix B Rear Signal Connector
- Appendix C SCXIbus Connector
- Appendix D SCXI-1121 Front Connector
- Appendix E SCXI-1121 Cabling
- Appendix F Revision A and B Photo and Parts Locator Diagrams
- Appendix G Technical Support Resources
- Glossary
- Index
- Figures
- Figure 2-1. SCXI-1121 General Parts Locator Diagram
- Figure 2-2. SCXI-1121 Detailed Parts Locator Diagram
- Figure 2-3. SCXI-1121 Front Connector Pin Assignment
- Figure 2-4. Ground-Referenced Signal Connection with High Common-Mode Voltage
- Figure 2-5. Floating Signal Connection Referenced to Chassis Ground for Better Signal-to-Noise Ratio
- Figure 2-6. Floating AC-Coupled Signal Connection
- Figure 2-7. AC-Coupled Signal Connection with High Common-Mode Voltage
- Figure 2-8. Assembling and Mounting the SCXI-1330 Connector-and-Shell Assembly
- Figure 2-9. Nulling Circuit
- Figure 2-10. Shunt Circuit
- Figure 2-11. SCXI-1320 Parts Locator Diagram
- Figure 2-12. SCXI-1328 Parts Locator Diagram
- Figure 2-13. SCXI-1321 Parts Locator Diagram
- Figure 2-14. SCXI-1121 Rear Signal Connector Pin Assignment
- Figure 2-15. SCANCLK Timing Requirements
- Figure 2-16. Slot-Select Timing Diagram
- Figure 2-17. Serial Data Timing Diagram
- Figure 2-18. Configuration Register Write Timing Diagram
- Figure 2-19. SCXI-1121 Module ID Register Timing Diagram
- Figure 3-1. SCXI-1121 Block Diagram
- Figure 3-2. SCXIbus Connector Pin Assignment
- Figure 3-3. Digital Interface Circuitry Block Diagram
- Figure 3-4. SCXI-1121 Digital Control
- Figure 3-5. Analog Input Block Diagram
- Figure 3-6. Analog Output Circuitry
- Figure 3-7. Single-Module Parallel Scanning
- Figure 3-8. Single-Module Multiplexed Scanning (Direct)
- Figure 3-9. Single-Module Multiplexed Scanning (Indirect)
- Figure 3-10. Multiple-Module Multiplexed Scanning
- Figure 3-11. Multiple-Chassis Scanning
- Figure B-1. SCXI-1121 Rear Signal Connector Pin Assignment
- Figure C-1. SCXIbus Connector Pin Assignment
- Figure D-1. SCXI-1121 Front Connector Pin Assignment
- Figure E-1. SCXI-1340 Installation
- Figure E-2. SCXI-1180 Rear Connections
- Figure E-3. SCXI-1180 Front Panel Installation
- Figure E-4. Cover Removal
- Figure F-1. Revision A and B SCXI-1121 Signal Conditioning Module
- Figure F-2. Revision A and B SCXI-1121 General Parts Locator Diagram
- Figure F-3. Revision A and B SCXI-1121 Detailed Parts Locator Diagram
- Tables
- Table 2-1. Digital Signal Connections, Jumper Settings
- Table 2-2. Jumper W33 Settings
- Table 2-3. Gain Jumper Allocation
- Table 2-4. Gain Jumper Positions
- Table 2-5. Filter Jumper Allocation
- Table 2-6. Voltage and Current Mode Excitation Jumper Setup
- Table 2-7. Maximum Load per Excitation Channel
- Table 2-8. Excitation Level Jumper Selection
- Table 2-9. Completion Network Jumpers
- Table 2-10. Trimmer Potentiometer and Corresponding Channel
- Table 2-11. Nulling Resistors and Corresponding Channel
- Table 2-12. Jumper Settings of the Nulling Circuits
- Table 2-13. Jumper Settings on the SCXI-1320 Terminal Block
- Table 2-14. Jumper Settings on the SCXI-1328 Terminal Block
- Table 2-15. Jumper Settings on the SCXI-1321 Terminal Block
- Table 2-16. SCXIbus to SCXI-1121 Rear Signal Connector to Data Acquisition Board Pin Equivalences
- Table 3-1. SCXIbus Equivalents for the Rear Signal Connector
- Table 3-2. Calibration Potentiometer Reference Designators
- Table 5-1. SCXI-1121 Rear Signal Connector Pin Equivalences
- Table E-1. SCXI-1121 and MIO-16 Pinout Equivalences
- Table E-2. SCXI-1341 and SCXI-1344 Pin Translations
- Table E-3. SCXI-1342 Pin Translations
- Table E-4. SCXI-1343 Pin Connections

Appendix C SCXIbus Connector
© National Instruments Corporation C-3 SCXI-1121 User Manual
SCXIbus Connector Signal Descriptions
Pin
Signal
Name
Description
A1, B1, C1, D1,
A2, D2,A3, B3,
C3, D3, A4, D4,
A5, B5, C5, D5,
A6, D6
GUARD Guard—Shields and guards the analog bus lines from noise.
B2 AB0+ Analog Bus 0+ —Positive analog bus 0 line. Used to multiplex
several modules to one analog signal.
C2 AB0– Analog Bus 0– —Negative analog bus 0 line. Used to multiplex
several modules to one analog signal.
C13-C17, A21,
B21, C21, D21
CHSGND Chassis Ground—Digital and analog ground reference.
C18 RSVD Reserved.
A19 RESET* Reset—When pulled low, reinitializes the module to its power-up
state. Totem pole. Input.
B19 MISO Master-In Slave-Out—Transmits data from the module to the
SCXIbus. Open collector. I/O.
C19 D*/A Data/Address—Indicates to the module whether address
information or data information is being sent to the module on
MOSI. Open collector. I/O.
D19 INTR* Interrupt—Active low. Causes data that is on MOSI to be written
to the Slot-Select Register in Slot 0. Open collector. Output.
A20, B20, C20,
D20
V– Negative Analog Supply— –18.5 to –25 V.
A22, B22, C22,
D22
V+ Positive Analog Supply— +18.5 to +25 V.
A23, D23 +5 V +5 VDC Source—Digital power supply.
B23 SPICLK Serial Peripheral Interface (SPI) Clock—Clocks the serial data
on the MOSI and MISO lines. Open collector. I/O.
C23 MOSI Master-Out Slave-In—Transmits data from the SCXIbus to the
module. Open collector. I/O.