DAQ DAQCard™-1200 User Manual Multifunction I/O Card for the PCMCIA Bus DAQCard-1200 User Manual October 1999 Edition Part Number 320936B-01
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Important Information Warranty The DAQ-Card-1200 is warranted against defects in materials and workmanship for a period of one year from the date of shipment, as evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace equipment that proves to be defective during the warranty period. This warranty includes parts and labor.
Contents About This Manual Organization of This Manual .........................................................................................ix Conventions Used in This Manual.................................................................................x National Instruments Documentation ............................................................................xi Related Documentation..................................................................................................
Contents Types of Signal Sources ................................................................... 3-6 Floating Signal Sources...................................................... 3-6 Ground-Referenced Signal Sources ................................... 3-6 Input Configurations......................................................................... 3-7 Differential Connection Considerations (DIFF Configuration) ......................................................
Contents Analog Output................................................................................................................4-11 Analog Output Circuitry..................................................................................4-11 Power-On State................................................................................................4-12 DAC Timing....................................................................................................4-12 Digital I/O ....................
Contents Figure 3-1. Figure 3-2. Figure 3-3. Figure 3-4. Figure 3-5. Figure 3-6. Figure 3-7. Figure 3-8. Figure 3-9. Figure 3-10. Figure 3-11. Figure 3-12. Figure 3-13. Figure 3-14. Figure 3-15. Figure 3-16. Figure 3-17. Figure 3-18. Figure 3-19. DAQCard-1200 I/O Connector Pin Assignments................................. 3-2 DAQCard-1200 Instrumentation Amplifier.......................................... 3-5 Differential Input Connections for Grounded Signal Sources ..............
About This Manual This manual describes the mechanical and electrical aspects of the DAQCard-1200 and contains information concerning its installation and operation. The DAQCard-1200 is a compact, low-cost, low-power analog input, analog output, digital, and timing I/O card for IBM PC/XT, PC AT, and compatible computers that are equipped with a Type II PC Card socket.
About This Manual • The Glossary contains an alphabetical list and description of terms used in this manual, including abbreviations, acronyms, metric prefixes, mnemonics, and symbols. • The Index contains an alphabetical list of key terms and topics in this manual, including the page where you can find each one. Conventions Used in This Manual The following conventions are used in this manual: <> Angle brackets enclose the name of a key on the keyboard—for example, .
About This Manual National Instruments Documentation The DAQCard-1200 User Manual is one piece of the documentation set for your data acquisition system. You could have any of several types of manuals, depending on the hardware and software in your system. Use the manuals you have as follows: • Getting Started with SCXI—If you are using SCXI, this is the first manual you should read.
About This Manual Related Documentation The following documents contain information that you may find helpful as you read this manual: DAQCard-1200 User Manual • Your NI-DAQ or LabVIEW software manuals for PC compatibles • Your computer operating manual, which explains how to insert cards into the PC Card slot • “Dither in Digital Audio” by John Vanderkooy and Stanley P. Lipshitz, Journal of the Audio Engineering Society, Vol. 35, No. 12, Dec.
1 Introduction This chapter describes the DAQCard-1200; lists what you need to get started, the optional software, and optional equipment; and explains how to unpack the DAQCard-1200. About the DAQCard-1200 Thank you for your purchase of the National Instruments DAQCard-1200. The DAQCard-1200 is a low-cost, low-power analog input, analog output, digital I/O, and timing I/O card for PCs equipped with a Type II PC Card slot.
Chapter 1 Introduction with the PC, is a versatile, cost-effective and portable platform for laboratory test, measurement, and control. The DAQCard-1200 is shipped with NI-DAQ, a National Instruments complete DAQ driver that handles every function listed on the data sheet for our DAQ hardware. Using NI-DAQ, you can start your application quickly and easily without having to program the card at the register level.
Chapter 1 Introduction LabVIEW and LabWindows/CVI Application Software LabVIEW and LabWindows/CVI are innovative program development software packages for data acquisition and control applications. LabVIEW uses graphical programming, whereas LabWindows/CVI enhances traditional programming languages. Both packages include extensive libraries for data acquisition, instrument control, data analysis, and graphical data presentation.
Chapter 1 Introduction Conventional Programming Environment (PC, Macintosh, or Sun SPARCstation) LabVIEW (PC, Macintosh, or Sun SPARCstation) LabWindows/CVI (PC or Sun SPARCstation) NI-DAQ Driver Software DAQ or SCXI Hardware Personal Computer or Workstation Figure 1-1. The Relationship between the Programming Environment, NI-DAQ, and Your Hardware Register-Level Programming The final option for programming any National Instruments DAQ hardware is to write register-level software.
Chapter 1 Introduction Optional Equipment You can use the following National Instruments products with your DAQCard-1200: • BNC-2081 • CB-50 or CB-50LP I/O connector block with a 0.5 or 1.0 m cable • ER-8, ER-16 electromechanical relays • PR50-50F or PR50-50M cables • SC-2042, SC-2043 strain gauge and RTD accessories • SCXI products For more information about optional equipment available from National Instruments, refer to your National Instruments catalog or call the office nearest you.
2 Installation and Configuration This chapter describes how to install and software configure the DAQCard-1200. Installation There are two basic steps to installing the DAQCard-1200. 1. You must have Card & Socket Services 2.0 (or a later version) on your computer. 2. Insert the DAQCard-1200 and attach the I/O cable. The DAQCard-1200 has two connectors—a 68-pin PCMCIA bus connector on one end and a 50-pin I/O connector on the other end.
Chapter 2 Installation and Configuration Figure 2-1 shows an example of a typical configuration. Portable Computer PCMCIA Socket I/O Cable CB-50 I/O Signals ent rum e war The Soft is the Inst ® AL TS ION MEN NATTRU INS Figure 2-1. A Typical Configuration for the DAQCard-1200 Configuration The DAQCard-1200 is completely software configurable; refer to your software manuals to install and configure your software.
Chapter 2 Installation and Configuration If you are using LabWindows/CVI, the software installation instructions are in Part 1, Introduction to LabWindows/CVI, of the Getting Started with LabWindows/CVI manual. After you have installed LabWindows/CVI, refer to Chapter 1, Configuring LabWindows/CVI, of the LabWindows/CVI User Manual for software configuration instructions. Then follow DAQ configuration instructions in your NI-DAQ user manual.
Chapter 2 Installation and Configuration Analog Input Mode The DAQCard-1200 has three different input modes—referenced single-ended (RSE), non-referenced single-ended (NRSE), and differential (DIFF). Single-ended configuration provides eight input channels. DIFF configuration provides four input channels. Table 2-2 describes these configurations. Table 2-2.
Chapter 2 Installation and Configuration NRSE Input (Eight Channels) NRSE input means that all signals are referenced to the same common mode voltage, which is allowed to float with respect to the analog ground of the DAQCard-1200. This common mode voltage is subsequently subtracted out by the instrumentation amplifier. NRSE configuration is useful when measuring ground-referenced signal sources. Considerations in using the NRSE configuration are discussed in Chapter 3, Signal Connections.
Chapter 2 Installation and Configuration Analog Output Polarity The DAQCard-1200 has two channels of analog output voltage at the front panel I/O connector. You can configure each analog output channel for either unipolar or bipolar output. A unipolar configuration has a range of 0 to 10 V at the analog output. A bipolar configuration has a range of –5 to +5 V at the analog output. If you select a bipolar range for a D/A conversion (DAC), the two’s complement coding is selected.
3 Signal Connections This chapter describes the signals on the DAQCard-1200 I/O connector. I/O Connector Figure 3-1 shows the pin assignments for the DAQCard-1200 I/O connector. This connector is attached to the ribbon cable that extends from the PC Card slot when the card is installed and the cable connected. Warning Connections, including power signals to ground and vice versa, that exceed any of the maximum ratings of input or output signals on the DAQCard-1200 can damage the DAQCard-1200 and the PC.
Chapter 3 Signal Connections ACH0 ACH2 ACH4 ACH6 AISENSE/AIGND AGND DGND PA1 PA3 PA5 PA7 PB1 PB3 PB5 PB7 PC1 PC3 PC5 PC7 EXTUPDATE* OUTB0 OUTB1 CLKB1 GATB2 +5 V 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 ACH1 ACH3 ACH5 ACH7 DAC0OUT DAC1OUT PA0 PA2 PA4 PA6 PB0 PB2 PB4 PB6 PC0 PC2 PC4 PC6 EXTTRIG EXTCONV* GATB0 GATB1 OUTB2 CLKB2 DGND Figure 3-1.
Chapter 3 Signal Connections Signal Connection Descriptions The following table describes the connector pins on the DAQCard-1200 front I/O connector by pin number and gives the signal name and the significance of each signal connector pin. Pins Direction Reference ACH<0..7> AI AGND Analog Channel 0 through 7—Analog input channels 0 through 7. 9 AISENSE/AIGND AI AGND Analog Input Sense/Analog Input Ground—Connected to AGND in RSE mode, analog input sense in NRSE mode.
Chapter 3 Pins Signal Connections Signal Name Direction Reference Description 45 CLKB1 DI DGND Clock B1—External control clock signal for counter B1. 46 OUTB2 DO DGND Counter B2—Voltage output signal of counter B2. 47 GATB2 DI DGND Gate B2—External control signal for gating counter B2. 48 CLKB2 DI DGND Clock B2—External control clock signal for counter B2. 49 +5 V DO DGND +5 Volts—Fused for up to 1 A of +5 V supply, but limit current to 250 mA.
Chapter 3 Signal Connections Table 3-1. Bipolar and Unipolar Analog Input Signal Range Versus Gain Input Signal Range Gain Setting Bipolar Unipolar 1 ±5 V 0 to 10 V 2 ±2.5 V 0 to 5 V 5 ±1 V 0 to 2 V 10 ±500 mV 0 to 1 V 20 ±250 mV 0 to 500 mV 50 ±100 mV 0 to 200 mV 100 ±50 mV 0 to 100 mV How you connect analog input signals to the DAQCard-1200 depends on how you configure the card analog input circuitry and the type of input signal source.
Chapter 3 Signal Connections The instrumentation amplifier applies gain, common-mode voltage rejection, and high-input impedance to the analog input signals connected to the DAQCard-1200. Signals are routed to the positive and negative inputs of the instrumentation amplifier through input multiplexers on the DAQCard-1200. The instrumentation amplifier converts two input signals to a signal that is the difference between the two input signals multiplied by the gain setting of the amplifier.
Chapter 3 Signal Connections The difference in ground potential between two instruments connected to the same building power system is typically between 1 mV and 100 mV but can be much higher if power distribution circuits are not properly connected. The connection instructions that follow for grounded signal sources eliminate this ground potential difference from the measured signal.
Chapter 3 Signal Connections When you configure the DAQCard-1200 for DIFF input, each signal uses two of the multiplexer inputs—one for the signal and one for its reference signal. Therefore, only four analog input channels are available when using the DIFF configuration. You should use the DIFF input configuration when any of the following conditions is present: • Input signals are low level (less than 1 V). • Leads connecting the signals to the DAQCard-1200 are greater than 15 ft.
Chapter 3 1 ACH 0 3 ACH 2 5 ACH 4 7 ACH 6 2 ACH 1 Common-Mode Noise, + Ground Potential Vcm 4 ACH 3 6 ACH 5 – 8 ACH 7 11 AGND Grounded Signal Source Signal Connections + Vs + – + – Vm Measured Voltage – Front I/O Connector DAQCard-1200 in DIFF Configuration Figure 3-3.
Chapter 3 Signal Connections Floating Signal Source 1 ACH 0 3 ACH 2 5 ACH 4 7 ACH 6 2 ACH 1 4 ACH 3 6 ACH 5 8 ACH 7 11 AGND + Vs 100 kΩ Bias Current Return Paths + – – Vm + Measured Voltage – 100 kΩ Front I/O Connector DAQCard-1200 in DIFF Configuration Figure 3-4. Differential Input Connections for Floating Sources The 100 kΩ resistors shown in Figure 3-4 create a return path to ground for the bias currents of the instrumentation amplifier.
Chapter 3 Signal Connections Single-Ended Connection Considerations Single-ended connections are those in which all DAQCard-1200 analog input signals are referenced to one common ground. The input signals are tied to the positive input of the instrumentation amplifier, and their common ground point is tied to the negative input of the instrumentation amplifier. When the DAQCard-1200 is configured for single-ended input (NRSE or RSE), eight analog input channels are available.
Chapter 3 Floating Signal Source Signal Connections 1 ACH 0 2 ACH 1 3 ACH 2 8 ACH 7 + + Vs – 9 + AISENSE/AIGND – 11 AGND Measured Voltage Vm – Front I/O Connector DAQCard-1200 in RSE Configuration Figure 3-5. Single-Ended Input Connections for Floating Signal Sources Single-Ended Connections for Grounded Signal Sources (NRSE Configuration) If you measure a grounded signal source with a single-ended configuration, you must configure the DAQCard-1200 in the NRSE input configuration.
Chapter 3 GroundReferenced Signal Source + 1 ACH 0 2 ACH 1 3 ACH 2 8 ACH 7 Signal Connections + Vs – 9 Common-Mode + Noise Vcm – AISENSE/AIGND Vm 11 AGND + Measured Voltage – – Front I/O Connector DAQCard-1200 in NRSE Input Configuration Figure 3-6.
Chapter 3 Signal Connections 2 V in unipolar mode. Vin+ should remain within a range of –6 to +11 V in either mode. Analog Output Signal Connections Pins 10 through 12 of the front connector are the analog output signals DAC0OUT, AGND, and DAC1OUT. DAC0OUT is the voltage output signal for analog output channel 0. DAC1OUT is the voltage output signal for analog output channel 1. AGND is the ground-reference point for both analog output channels and analog input.
Chapter 3 Signal Connections Digital I/O Signal Connections ! Caution The DAQCard-1200 DIO lines are not pulled up or pulled down. If you are using these lines as digital outputs, add 10 kΩ resistors to +5 V or DGND (depending on your application) to the DIO line(s) you are using. Pins 13 through 37 of the front connector are digital I/O signal pins. Digital I/O on the DAQCard-1200 uses the 82C55A integrated circuit.
Chapter 3 Signal Connections Figure 3-8 illustrates signal connections for three typical digital I/O applications. Port C PC <0..7> 22 PB0 Port B PB <0..7> TTL Signal 29 PB7 +5 V 13 +5 V LED DGND Port A PA <0..7> 30 PA0 I/O Connector DAQCard-1200 Figure 3-8. Digital I/O Connections In Figure 3-8, port A is configured for digital output, and ports B and C are configured for digital input.
Chapter 3 Signal Connections Port C Pin Connections The signals assigned to port C depend on how the 82C55A is configured. In mode 0 or no handshaking configuration, port C is configured as two 4-bit I/O ports. In modes 1 and 2, or handshaking configuration, port C is used for status and handshaking signals with zero, two, or three lines available for general-purpose I/O. Table 3-3 summarizes the port C signal assignments for each configuration.
Chapter 3 Signal Connections Timing Specifications Use the handshaking lines STB* and IBF to synchronize input transfers. Use the handshaking lines OBF* and ACK* to synchronize output transfers. The following signals are used in the timing diagrams shown later in this chapter: Name Type Description STB* Input Strobe Input—A low signal on this handshaking line loads data into the input latch.
Chapter 3 Signal Connections Mode 1 Input Timing Figure 3-9 shows the timing specifications for an input transfer in mode 1. T1 T2 T4 STB * T7 T6 IBF INTR RD * T3 T5 DATA Name Description Minimum Maximum T1 STB* pulse width 100 — T2 STB* = 0 to IBF = 1 — 150 T3 Data before STB* = 1 20 — T4 STB* = 1 to INTR = 1 — 150 T5 Data after STB* = 1 50 — T6 RD* = 0 to INTR = 0 — 200 T7 RD* = 1 to IBF = 0 — 150 All timing values are in nanoseconds. Figure 3-9.
Chapter 3 Signal Connections Mode 1 Output Timing Figure 3-10 shows the timing specifications for an output transfer in mode 1. T3 WRT* T4 OBF* T1 INTR T6 T5 ACK* DATA T2 Name Description Minimum Maximum T1 WRT* = 0 to INTR = 0 — 250 T2 WRT* = 1 to output — 200 T3 WRT* = 1 to OBF* = 0 — 150 T4 ACK* = 0 to OBF* = 1 — 150 T5 ACK* pulse width 100 — T6 ACK* = 1 to INTR = 1 — 150 All timing values are in nanoseconds. Figure 3-10.
Chapter 3 Signal Connections T1 WRT * T6 OBF * INTR T7 ACK * T3 STB * T10 T4 IBF RD * T2 T5 T8 T9 DATA Name Description Minimum Maximum T1 WRT* = 1 to OBF* = 0 — 150 T2 Data before STB* = 1 20 — T3 STB* pulse width 100 — T4 STB* = 0 to IBF = 1 — 150 T5 Data after STB* = 1 50 — T6 ACK* = 0 to OBF = 1 — 150 T7 ACK* pulse width 100 — T8 ACK* = 0 to output — 150 T9 ACK* = 1 to output float 20 250 T10 RD* = 1 to IBF = 0 — 150 All timing values are in nanosec
Chapter 3 Signal Connections DAQ and General-Purpose Timing Signal Connections Pins 38 through 48 of the front connector are connections for timing I/O signals. The DAQCard-1200 timing I/O uses two 82C53 counter/timer integrated circuits. One circuit, designated 82C53(A), is used exclusively for DAQ timing, and the other, 82C53(B), is available for general use. You can use pins 38 through 40 and pin 43 to carry external signals for DAQ timing in place of the dedicated 82C53(A).
Chapter 3 Signal Connections In the posttrigger mode, EXTTRIG serves as an external trigger that initiates a data acquisition sequence. When you use counter A0 to time sample intervals, a rising edge on EXTTRIG starts counter A0 and the data acquisition sequence. When you use EXTCONV* to time sample intervals, data acquisition is enabled on a rising edge of EXTTRIG followed by a rising edge on EXTCONV*. The first conversion occurs on the next falling edge of EXTCONV*.
Chapter 3 Signal Connections Figure 3-14 shows a pretrigger data acquisition timing sequence using EXTTRIG and EXTCONV*. The data acquisition operation has been initiated through software. Notice that the sample counter has been programmed to allow five conversions after the rising edge on the EXTTRIG signal. Additional transitions on the EXTTRIG line have no effect until you initiate a new data acquisition sequence. tw VIH tw 50 ns minimum tw EXTTRIG VIL EXTCONV* CONVERT Figure 3-14.
Chapter 3 Signal Connections OUTB1 tw = 50 ns td = 50 ns EXTCONV* CONVERT GATE ADC CH CH1 CH0 CH1 CH0 Figure 3-15. Interval-Scanning Signal Timing Use the final external control signal, EXTUPDATE*, to externally control updating the output voltage of the 12-bit DACs and/or to generate an externally timed interrupt. There are two update modes—immediate update and delayed update. In immediate update mode the analog output is updated as soon as a value is written to the DAC.
Chapter 3 Signal Connections this case is triggered by a low level on the EXTUPDATE* line. The counter-interrupt signal interrupts the PC. This interrupt is generated on the rising edge of EXTUPDATE*. The DACWRT signal writes a new value to the DAC. EXTUPDATE* tw 50 ns min DAC OUTPUT UPDATE Counter Interrupt DACWRT Figure 3-16. EXTUPDATE* Signal Timing for Updating DAC Output The following rating applies to the EXTCONV*, EXTTRIG, OUTB1, and EXTUPDATE* signals.
Chapter 3 Signal Connections which has an internal 2 MHz clock. Refer to the DAQCard-1200 Register-Level Programmer Manual for programming information. The GATE, CLK, and OUT signals for counters B1 and B2 are available at the I/O front connector. The GATE and CLK pins are internally pulled up to +5 V through a 100 kΩ resistor. Refer to Appendix A, Specifications, for signal voltage and current specifications.
Chapter 3 Signal Connections Pulsewidth measurement is performed by level gating. The pulse you want to measure is applied to the counter GATE input. The counter is loaded with the known count and is programmed to count down while the signal at the GATE input is high. The pulse width equals the counter difference (loaded value minus read value) multiplied by the CLK period. Perform time-lapse measurement by programming a counter to be edge gated.
Chapter 3 Signal Connections +5 V 10 kΩ CLK OUT GATE Signal Source Gate Source Counter 13 DGND I/O Connector DAQCard-1200 Figure 3-18.
Chapter 3 Signal Connections Figure 3-19 shows the timing requirements for the GATE and CLK input signals and the timing specifications for the OUT output signals of the 82C53.
Chapter 3 Signal Connections Power Connections Pin 49 of the I/O connector supplies +5 V from the DAQCard-1200 power supply. This pin is referenced to DGND. You can use the +5 V to power external digital circuitry. • Warning Power rating 250 mA at +5 V maximum, fused to 1 A Do not directly connect this +5 V power pin to analog or digital ground or to any other voltage source on the DAQCard-1200 or any other device. Doing so can damage the DAQCard-1200 or your PC.
4 Theory of Operation This chapter explains the operation of each functional unit of the DAQCard-1200. Functional Overview The block diagram in Figure 4-1 shows a functional overview of the DAQCard-1200.
Chapter 4 Theory of Operation The major components of the DAQCard-1200 are as follows: • PC Card I/O channel interface circuitry • Analog input circuitry • Analog output circuitry • Digital I/O 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.
Chapter 4 Theory of Operation When you first insert the card into your computer, the system examines information stored in the DAQCard-1200 Card Information Structure (CIS). This data is used to configure the card appropriately for the system in which it is used. When the system has assigned the card to a section of memory, it updates the PC Card control registers and initializes the card.
Theory of Operation GATEB2 CLKB2 GeneralPurpose Counter GATEB2 CLKB2 OUTB2 OUTB2 GATEB1 OUTB0 GATEB1 CLKB1 MUX CLKB1 0AKLC Scan Interval/ GeneralPurpose Counter OUTB1 OUTB1 OUTB0 GATEB0 OUTB0 GATEB0 1 MHz Source MUX CTR RD CTR WRT Data I/O Connector Timebase Extension/ GeneralPurpose Counter 2 MHz Source 8 CLKA0 GATEA0 CLKB0 82C53 Counter/Timer Group B Sample Interval Counter OUTB1 Decode Circuitry Chapter 4 OUTA0 CLKA1 EXTCONV* Sample Counter A/D Conversion Logic GATEA1 OUTA1
Chapter 4 Theory of Operation Each 82C53 contains three independent 16-bit counter/timers and one 8-bit Mode Register. Each counter has a CLK input pin, a GATE input pin, and an OUT output pin. You can program all three counter/timers to operate in several useful timing modes. The first group of counter/timers is called Group A and includes A0, A1, and A2.
A/D Data 12 Data 1k Sample 12 A/D FIFO Mux GAIN0 GAIN1 GAIN2 6 Dither EXTTRIG EXTCONV* OUTB1 Data 8 WRT/RD Dither Circuitry External Trigger CON V Gain Select/ Mux Counter Dither Enable DAQ Timing Counter/Timer Signals Data 8 PCMCIA I/O Channel 12-Bit ADC Decode Circuitry Sampleand-Hold Amp PCMCIA Interface Programmable Gain Amp Convert ACH0 ACH1 ACH2 ACH3 ACH4 ACH5 ACH6 ACH7 AISENSE/ AIGND Theory of Operation I/O Connector Chapter 4 External Convert Output B1 Figure 4-4.
Chapter 4 Theory of Operation can scan any number of channels from eight to two. Notice that the same gain setting is used for all channels in the scan sequence. The programmable gain amplifier applies gain to the input signal, allowing an analog input signal to be amplified before being sampled and converted, thus increasing measurement resolution and accuracy. The instrumentation amplifier gain is software selectable. The DAQCard-1200 provides gains of 1, 2, 5, 10, 20, 50, and 100.
Chapter 4 Theory of Operation with a range of –2,048 to +2,047. In this mode, the MSB of the ADC result is modified to make it two’s complement. The output from the ADC is then sign extended to 16 bits, causing either a leading 0 or a leading F (hex) to be added, depending on the coding and the sign. Thus, data values read from the FIFO are 16 bits wide.
Chapter 4 Theory of Operation Interval Data Acquisition In an interval data acquisition operation, a new period called the interval cycle is defined. Within each interval cycle, a predefined number of samples is taken at regular sample intervals and conversions are stopped for the remainder of the interval cycle. A data acquisition operation consists of back-to-back interval cycles.
Chapter 4 Theory of Operation For multiple-channel data acquisition, observing the data acquisition rates in Table 4-2 ensures 12-bit accuracy. Table 4-1. Analog Input Settling Time Versus Gain Gain Setting Settling Time Recommended 10 µs max 1, 2, 5, 10 20 12 µs typ, 15 µs max 50 25 µs typ, 30 µs max 100 60 µs typ, 80 µs max Table 4-2. DAQCard-1200 Maximum Recommended Data Acquisition Rates Acquisition Mode Gain Setting Sampling Rate Single channel 1, 2, 5, 10, 20, 50, 100 100.
Chapter 4 Theory of Operation Analog Output The DAQCard-1200 has two channels of 12-bit D/A output. Each analog output channel can provide unipolar or bipolar output. The DAQCard-1200 also contains timing circuitry for waveform generation timed either externally or internally. Figure 4-5 shows the analog output circuitry.
Chapter 4 Theory of Operation Power-On State Both analog outputs reach 0 V approximately 110 ms after card insertion. During this 110 ms period, the output voltage can swing from +2 to –5 V. Warning Disconnect the analog outputs from the system before inserting the card in the PC Card slot. This step ensures that you do not damage your system during the 110 ms before the output reaches 0 V. DAC Timing There are two ways you can update the DAC voltages.
Chapter 4 Theory of Operation Digital I/O The digital I/O circuitry has an 82C55A integrated circuit. The 82C55A is a general-purpose programmable peripheral interface (PPI) containing 24 programmable I/O pins. These pins represent the three 8-bit I/O ports (A, B, and C) of the 82C55A, as well as PA<0..7>, PB<0..7>, and PC<0..7> on the DAQCard-1200 I/O connector. Figure 4-6 shows the digital I/O circuitry. Decode Circuitry 8 DIO RD/WRT 8 PB<0..
5 Calibration This chapter discusses the calibration procedures for the DAQCard-1200 analog I/O circuitry. However, the DAQCard-1200 is factory calibrated, and National Instruments can recalibrate your card if necessary. To maintain the 12-bit accuracy of the DAQCard-1200 analog input and analog output circuitry, recalibrate at 6-month intervals. There are two ways to perform calibrations. • Use the NI-DAQ Calibrate_1200 function. This is the simpler method.
Chapter 5 Calibration Calibration at Higher Gains The DAQCard-1200 has a maximum gain error of 0.8%. This means that if the card is calibrated at a gain of 1, and if the gain is switched to 100, a maximum of 32 LSB error may result in the reading.
Chapter 5 Calibration When you perform analog input calibration, you must first configure the ADC for referenced single-ended (RSE) mode and for the correct polarity at which you want to perform data acquisition. When you perform analog output calibration, you must first configure the analog input circuitry for RSE and for bipolar polarity, and you must configure the analog output circuitry for the correct polarity at which you want to perform output waveform generation.
A Specifications This appendix lists the specifications for the DAQCard-1200. These specifications are typical at 25 °C unless otherwise noted. Analog Input Input Characteristics Number of channels ............................... 8 single-ended, 8 pseudodifferential or 4 differential, software selectable Resolution .............................................. 12 bits, 1 in 4,096 Max single-channel sampling rate .........
Appendix A Specifications Maximum working voltage (signal + common mode) ........................Negative input/AISENSE should remain within ±6 V (bipolar) or –6 to 2 V (unipolar) of AGND Overvoltage protection ...........................±35 V powered on and ±25 V powered off Inputs protected ...................................... FIFO buffer size......................................1,024 samples Data transfers ..........................................Interrupts, programmed I/O Dither ......
Appendix A Specifications Input bias current ................................... ±100 pA Input offset current................................. ±100 pA CMRR .................................................... 70 dB, DC to 60 Hz Dynamic Characteristics Bandwidth Small signal (–3 dB) Gain Bandwidth 1–10 250 kHz 20 150 kHz 50 60 kHz 100 30 kHz Settling time to full scale step Accuracy Gain ±0.
Appendix A Specifications Stability Recommended warm up time .................15 minutes Offset temperature coefficient Pre-gain............................................±15 µV/°C Post-gain ..........................................±100 µV/°C Gain temperature coefficient ..................±40 ppm/°C Analog Output Output Characteristics Number of Channels ...............................2 voltage Resolution ...............................................12 bits, 1 in 4,096 Max update rate ...............
Appendix A Specifications Voltage Output Ranges .................................................... 0–10 V, ±5 V software selectable Output coupling...................................... DC Output impedance .................................. 0.5 Ω typ Current drive ......................................... 1 mA max per channel Protection ............................................... 80 mA momentary short-circuit protection to ground Power on state 0 to 110 ms......................................
Appendix A Specifications Digital logic levels Level Min Max Input low voltage –0.3 V 0.8 V Input high voltage 2.2 V 5.3 V Output low voltage (Iout = 2.5 mA) — 0.4 V Output high voltage (Iout = –40 µA) (Iout = –2.5 mA) 4.2 V 3.7 V — — –10 µA 10 µA Output leakage current 0 ≤ Vout ≤ Vcc Protection................................................–0.5 to 5.5 V powered on, ±0.5 V powered off Handshaking ...........................................3 wire, 2 port Data transfers ..................
Appendix A Specifications Protection ............................................... –0.5 to 5.5 V powered on, ±0.5 V powered off Resolution Counters/timers ............................... 16 bits Compatibility ......................................... TTL Base clocks available ............................. 2 MHz Base clock accuracy ............................... ±50 ppm max Max source frequency ............................ 8 MHz Min source pulse duration......................
Appendix A Specifications Environment Operating temperature ............................0 to 50 °C Storage temperature ................................–55 to 150 °C Relative humidity ...................................
Differences among the Lab-PC+, the DAQPad-1200, and the DAQCard-1200 B This appendix contains a summary of the functional differences among the Lab-PC+, the DAQPad-1200, and the DAQCard-1200. The Lab-PC+ is a plug-in DAQ board for PCs. It has jumpers for allocating of bus resources such as base address, interrupt, and DMA channels, as well as analog input/output resources such as input/output mode and polarity. It also has potentiometers for calibration.
Appendix B Differences among the Lab-PC+, the DAQPad-1200, and the DAQCard-1200 The following table summarizes the differences among the three products.
C Power-Management Modes This appendix describes the power-management modes of the DAQCard-1200. • Normal Mode—This is the normal operating mode of the DAQCard-1200 in which all the circuits are fully functional. This mode draws about 150 mA from the 5 V supply (about 750 mW). • Power-Down Mode—In this mode, the digital circuitry is powered on and is functional. The analog input and output circuits are powered down by setting the PWRDOWN bit in the PCMCIA Card Configuration and Status Register.
Appendix C Power-Management Modes Table C-1. DAQCard-1200 Power-Management Modes (Continued) Normal Mode Power-Down Mode Calibration Circuitry Functional. Both analog input and analog output can be fully calibrated. The CALDACs default to 0 V. Nonfunctional. Draws negligible power. 5 V supply is ideally zero, but gets negligible voltage. The CALDACs default to 0 V. Calibration constants (digital values) written into the CALDAC are not preserved and must be rewritten after entering normal mode.
PC Card Questions and Answers D This appendix contains a list of common questions and answers relating to PC Card operation. The questions are grouped according to the type of information requested. You may find this information useful if you are having difficulty with the PC Card system software configuration. Configuration 1. Do I need to use my PC Card configuration utility to configure the National Instruments PC Cards? No.
Appendix D PC Card Questions and Answers 2. My computer locks up when I use a PC Card. What should I do? This usually happens because Card Services allocated an unusable interrupt level to the PC Card. For example, on some computers, interrupt level 11 is not routed to PC Cards. If Card Services is not aware of this, it may assign interrupt 11 to a PC Card even though the interrupt is not usable. When a call uses the interrupt, the interrupt never occurs, and the computer locks up waiting for a response.
Appendix D PC Card Questions and Answers are being used for ROM access, then you know that C8000–D3FFF is an invalid range for Card Services and should be changed to CA000–D3FFF. 3. How can I find usable I/O addresses? Finding usable I/O addresses is done by trial and error. Of the three resources used—memory, I/O, interrupts—I/O conflicts will be low. You can use either DAQCONF.EXE in DOS or WDAQCONF in Windows to diagnose I/O space conflicts.
Appendix D PC Card Questions and Answers Resource Conflicts 1. How do I resolve conflicts between my memory manager and Card Services? Card Services can usually use memory space that is not being used for real RAM on the system. Even when this is the case, you should still exclude the memory addresses used by Card Services from use by any memory manager that may be installed.
Technical Support Resources E This appendix describes the comprehensive resources available to you in the Technical Support section of the National Instruments Web site and provides technical support telephone numbers for you to use if you have trouble connecting to our Web site or if you do not have internet access. NI Web Support To provide you with immediate answers and solutions 24 hours a day, 365 days a year, National Instruments maintains extensive online technical support resources.
Software-Related Resources • Instrument Driver Network—A library with hundreds of instrument drivers for control of standalone instruments via GPIB, VXI, or serial interfaces. You also can submit a request for a particular instrument driver if it does not already appear in the library. • Example Programs Database—A database with numerous, non-shipping example programs for National Instruments programming environments.
Glossary Prefix Meanings Value p- pico- 10 –12 n- nano- 10 –9 µ- micro- 10 – 6 m- milli- 10 –3 k- kilo- 10 3 M- mega- 10 6 G- giga- 10 9 t- tera- 10 12 Numbers/Symbols ° degrees Ω ohms % percent A A amperes AC alternating current ACH analog input channel signal A/D analog-to-digital ADC analog-to-digital converter—an electronic device, often an integrated circuit, that converts an analog voltage to a digital number © National Instruments Corporation G-1 DAQCard-1
Glossary AIGND analog input ground signal AWG American Wire Gauge B BCD binary-coded decimal C C Celsius CE card enable signal CLK clock input signal CMOS complementary metallic oxide semiconductor CMRR common-mode rejection ratio—a measure of an instrument’s ability to reject interference from a common-mode signal, usually expressed in decibels (dB) D D/A digital-to-analog DAQ data acquisition—(1) collecting and measuring electrical signals from sensors, transducers, and test probes or
Glossary DMA direct memory access—a method by which data can be transferred to/from computer memory from/to a device or memory on the bus while the processor does something else. DMA is the fastest method of transferring data to/from computer memory.
Glossary H hex hexadecimal Hz hertz—the number of scans read or updates written per second I in.
Glossary O OUT output signal P PCMCIA an expansion bus architecture that has found widespread acceptance as a de facto standard in notebook-size computers. It originated as a specification for add-on memory cards written by the Personal Computer Memory Card International Association.
Glossary V V volts VCC positive supply voltage from the PCMCIA bus (usually +5V) VDC volts, direct current VI virtual instrument—(1) a combination of hardware and/or software elements, typically used with a PC, that has the functionality of a classic stand-alone instrument (2) a LabVIEW software module (VI), which consists of a front panel user interface and a block diagram program VIH volts, input high VIL volts, input low Vin volts in VOH volts, output high VOL volts, output low DAQCard
Index Numbers polarity configuration, 2-3 settings (table), 2-3 power-management modes (table), C-1 specifications, A-1 to A-4 amplifier characteristics, A-2 to A-3 dynamic characteristics, A-3 input characteristics, A-1 to A-2 stability, A-4 transfer characteristics, A-2 theory of operation, 4-5 to 4-8 analog input modes configurations differential connection considerations, 3-7 to 3-8 floating signal sources, 3-9 to 3-10 ground-referenced signal sources, 3-8 to 3-9 recommended input configurations (table
Index B grounded signal sources, 3-8 to 3-9 single-ended connections, 3-11 to 3-13 when to use, 3-8 exceeding maximum input voltage ratings (warning), 3-4 floating signal sources, 3-6 ground-referenced signal sources, 3-6 to 3-7 input configurations, 3-7 to 3-14 instrumentation amplifier, 3-5 to 3-6 pins, 3-4 recommended input configurations (table), 3-7 single-ended connections floating signal sources (RSE configuration), 3-11 to 3-12 grounded signal sources (NRSE configuration), 3-12 to 3-13 purpose and
Index D data acquisition operation, 4-8 interval data acquisition, 4-9 data acquisition timing connections, 3-22 to 3-26. See also general-purpose timing signal connections.
Index F digital I/O signal connections illustration, 3-16 pins, 3-15 Port C pin connections, 3-17 timing specifications, 3-18 to 3-21 mode 1 input timing, 3-19 mode 1 output timing, 3-20 mode 2 bidirectional timing, 3-20 to 3-21 documentation conventions used in manual, x National Instruments documentation, xi organization of manual, ix-x related documentation, xii dynamic characteristics analog input specifications, A-3 analog output specifications, A-5 floating signal sources differential connections,
Index I N IBF signal (table), 3-18 input configurations differential connection considerations, 3-7 to 3-8 floating signal sources differential connections, 3-9 to 3-10 recommended input configurations (table), 3-7 ground-referenced signal sources differential connections, 3-8 to 3-9 recommended input configurations (table), 3-7 installation DAQCard-1200, 2-1 unpacking the DAQCard-1200, 1-5 instrumentation amplifier, 3-5 to 3-6 interval scanning data acquisition description, 3-24 multiple-channel interva
Index R PC Card configuration, D-1 I/O channel interface circuitry block diagram, 4-2 theory of operation, 4-2 to 4-3 operation, D-1 to D-2 resource conflicts, D-4 resources, D-2 to D-3 PC<0..7> signals description (table), 3-3 digital I/O signal connections, 3-15 physical specifications, A-7 pin assignments for I/O connector (figure), 3-2 polarity analog input, 2-3 analog output, 2-6 bipolar and unipolar signal range vs.
Index software programming choices, 1-2 to 1-4 LabVIEW and LabWindows/CVI, 1-3 NI-DAQ driver software, 1-3 to 1-4 register-level programming, 1-4 software-related resources, E-2 specifications analog input, A-1 to A-4 amplifier characteristics, A-2 to A-3 dynamic characteristics, A-3 input characteristics, A-1 to A-2 stability, A-4 transfer characteristics, A-2 analog output, A-4 to A-5 dynamic characteristics, A-5 output characteristics, A-4 stability, A-5 transfer characteristics, A-4 voltage output, A-5
Index transfer characteristics analog input specifications, A-2 analog output specifications, A-4 analog output, 4-11 to 4-12 circuitry, 4-11 DAC timing, 4-12 power-on state, 4-12 block diagram of DAQCard-1200, 4-1 digital I/O, 4-13 functional overview, 4-1 to 4-2 PC card I/O channel interface circuitry, 4-2 to 4-3 timing, 4-3 to 4-5 time-lapse measurement, 3-28 timing circuitry illustration, 4-4 theory of operation, 4-3 to 4-5 timing I/O specifications, A-6 to A-7 timing signal connections.
