Omega-engineering DAQ-12 Manual do Utilizador

INTERFACE CARDS FOR PERSONAL COMPUTERSDAQ-12Data Acquisition AdapterFor 16 bit ISA compatible machinesUsers ManualOMEGA ENGINEERING, INC. TEL: (2

2. Circuit Board Description and ConfigurationThe base address of the DAQ-12 is selected using switches SW1 and SW2. The operatingmode of the DAQ-1

The amplifier stage of the A/D converter circuit performs two functions: (1) amplifies lowlevel input signals and (2) converts this input signal into

Table 2-1 details the available gain settings and resulting input ranges for the various input configurations. Note that the 'gai

The final stage of the A/D converter circuit is the A/D converter IC. The converter must beconfigured for unipolar or bipolar input voltages as shown

n/a0000 1111 1111 1111100000 0111 1111 11110000 1000 0000 000050000 0100 0000 00000000 0100 0000 00002.50000 0000 0000 00000000 000

The D/A converter channels may also be operated in unipolar mode: 0 to +5 volts, or bipolarmode: -5 to +5 volts. The output mode is selected using jum

2.3 Digital Input/OutputThe DAQ-12 offers four bits of digital output and four bits of digital input forcontrol/monitoring of external digital devices

2.5 Clock SelectionThe DAQ-12 is equipped with a programmable clock circuit to produce data sampling ratesindependent from the clock rate of the host

2.5.1 Internal ClockSampling rates for the internal clock can be calculated using the following equation: t = 100ns * [N1*N2] o

When configured for a 48-bit divider, the first sampling period will be slightly longer thanthe others because the first clock period is required to

WARRANTY/DISCLAIMEROMEGA ENGINEERING, INC., warrants this unit to be free of defects in materials and workmanship for a period of 13months from the da

When the multi-function timer is used as a pre-divider, the frequency of the external clockinput may be varied from DC to 10 MHz as long as the high p

2.7 Direct Memory AccessDirect Memory Access (DMA) transfers provide a way of transferring data from theDAQ-12's A/D converter into the persona

2.8 InterruptsThe DAQ-12 is capable of generating an interrupt from one of four sources:1. End of conversion signal2. DMA terminal count3. Multi-funct

3. External ConnectionsThe DAQ-12 is equipped with a high density 62-pin connector as shown in Figure 3-1.2 - CH1+ 4 - CH2- (CH10+)6 - CH4

CHx-, CHx+ : Analog inputs to the analog to digital converter. When using differential inputmode, eight input channels are available (CH0+ to C

4. Register Description and ProgrammingThe DAQ-12 uses 16 consecutive I/O address locations in the range 0 to FFFFH. The cardutilizes these address

INT2, INT1 and INT0 control the DAQ-12 interrupt source.INT2 INT1 INT0 DESCRIPTION0 0 0 Interrupt disabled1 0 0 Interrupt timer 21 0 1 Interrupt on

VALID - when set, logic 1, indicates at least one data sample was lost because it was read bythe personal computer before the next sample was converte

4.1.4 D/A Converter 0 RegisterAn output to this register causes the lower twelve bits of data to be converted to an analogoutput on D/A converter chan

4.2 Programming the 8254 Counter/TimerThis section provides programming information for the 8254 counter/timer as implementedon the DAQ-12. For more

Declaration of ConformityManufacturer's Name: Omega Engineering, Inc.Manufacturer’s Address: One Omega DriveStamford, CT 06907-0047Application o

Counter 1 - Clock rate register (high word)operating mode: 2minimum count value: 2configuration byte: 0 / 1 / 1 / 1 / 0 / 1 / 0 / 0 = 74H

DAQ-12 Users ManualVersion 2.20January 28, 1999Part No. 940-0030-220

OMEGAnet On-line Service: Internet e-mail: http://www.omega.com [email protected] North Americ

United Kingdom: One Omega Drive, River Bend Technology DriveISO 9002 CertifiedNorthbank, Irlam, ManchesterM44 5EX, England Tel: 44 (161) 777-6611FAX:

Table of Contents294.2 Programming the 8254 Counter/Timer...284.1.9 8254 Control Word/Status Register...

List of Figures and Tables25Table 4-1. DAQ-12 Address Map...15Table 2-3. D/A Converter Mode Select

1. IntroductionThe DAQ-12 is a high speed data acquisition adapter for IBM AT and compatible machinesoffering eight differential analog input channel

1.2 DAQ-12 SpecificationsDACK 5, 6, 7DRQ 5, 6, 7DMA Levels:IRQ 2, 3, 4. 5, 6, 7, 10, 11, 12, 14, 15Interrupt Levels:0000H - FFFFHI/O Address Range:ISA