Measurement Computing ADAC/5500 Series - Manual (Page 9)

ADAC Series PCI Boards 196 - 4 - ADAC/5500 Series User Manual 908
1.2.1 Analog Inputs
The ADAC/5500MF has 8 single-ended analog inputs multiplexed to a 12-bit A/D converter. The input multiplexer is
supported by 176 elements of channel list RAM, which allows the board to access channels in any order. The 12-bit
A/D has a maximum throughput of 100 kHz and a programmable input range of
±10 V or 0-10 V. An A/D Pacer Clock
is provided to allow sampling rates from 0.0009 Hz to 100 kHz. An on-board Counter/Timer circuit provides two
counters and two timers dedicated to user connections.
The ADAC/5501MF, ADAC/5502MF, ADAC/5503HR and ADAC/5504HR models support 16 single-ended / pseudo-
differential analog inputs, or 8 differential analog inputs (expandable to 64) multiplexed to a 12 or 16-bit A/D
converter. The input multiplexer is supported by a 176 element channel gain RAM which allows the board to select
gain on a per channel basis and to access channels in any order. The 12-bit A/D has maximum throughput of 100 kHz
and the 16-bit A/D has a maximum throughput of 200 kHz. An A/D Pacer clock is provided to allow sampling rates
from 0.0009Hz to 200 kHz.
1.2.1.1 4-20mA Current Loop Inputs – n/a
1.2.2 Analog Outputs
The ADAC/5501MF, ADAC/5502MF, ADAC/5503HR and ADAC/5504HR models may be equipped with two
optional clocked DACs (D/A). Both DAC channels are DC accurate with 16-bit resolution and
200 kHz throughput. The output ranges of the DACs are programmable to
±10 V or 0 to +10 V. A Pacer clock is
provided to allow sampling rates from 0.0009Hz to 200 kHz.
1.2.3 Digital I/O
All boards have 16 lines of TTL level digital I/O programmable in 8-bit ports as either inputs or outputs. All 16 lines
are brought out via the main 68-pin SCSI III connector, user accessible at the back of the PC.
Two additional 40 pin headers on the ADAC/5501MF, ADAC/5502MF, ADAC/5503HR and ADAC/5504HR models
(internal to the PC) provide access to an additional thirty two 5 V CMOS/LSTTL compatible digital lines,
programmable in 16-bit ports as either inputs or outputs. Both sets of digital I/O lines may be brought to the back of the
computer with optional adapter connectors that are compatible with the ADAC line of isolated digital I/O panels.
1.2.4 Counters 0 and 1
Counter 0 and 1 can provide either cumulative or incremental counting capabilities. The counters are capable of
counting 5 V LSTTL rising edges to a maximum count of 131071 decimal.
1.2.5 Timers 0 and 1
Timer0 and Timer1 provide a 50% duty cycle square wave 5 V LSTTL output with an output frequency range of
7.7 Hz to 500 kHz. The Timer’s output frequency is based on a 1 MHz oscillation with a divisor of 1 to 65536 decimal.
1.2.6 PCI Interface
The ADAC/5500 Series boards communicate to the PCI bus through an ADAC PCI interface controller. The boards are
fully Plug&Play compatible with no switches, potentiometers, or jumpers. The boards feature digitally calibrated A/D
and D/A’s, and Plug&Play compatibility to provide automatic integration into the PC’s configuration when first
installed. The interface also provides access to all on-board registers for software configuration of all on-board
functions. For maximum performance, the ADAC/5500 boards feature a 32-bit bus-mastering DMA engine on the
ADC and DAC hardware to provide high-speed transfers between the board and system memory.