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72-MDC-32ADC Datasheet, PDF (1/2 Pages) Grayhill, Inc – CONTROLLERS MicroDAC (Optomux)
System 50
CONTROLLERS
MicroDAC (Optomux)
FEATURES
• Each Unit Controls/Monitors up to
32 Analog (G5 Only) and/or Digital
I/O Modules
• Executes On-Board Programs
Created With Borland C
• Network up to 64 MicroDACs per
Host Serial Port, Each Separated
by as Much as 4000 Feet
• Communicate Over RS-422/485 at
Speeds From 1200 Bd to 115.2 KB
• 100% Optomux™ Compatible, With
Expanded Command Set
• I/O Update Rates of 500 µSec per
32 Digital I/O, and 10 mS per
Analog Input or 2 Analog Outputs
• BASIC and C Drivers for the PC
• DIN Rail or Panel Mountable Metal
Enclosure
• Hardware Expansion With SBX Port
• Real Time Clock Option (Y2K
Compliant)
APPLICATIONS
Stand Alone Control
Local Control & I/O
Remote I/O
Distributed I/O
SCADA
RTU
COMMUNICATIONS
The host PC and MicroDAC(s) communicate
serially over one or two pair of twisted wires per
RS-422/485 in either a multi-drop or repeat
configuration. They use Optomux™ ASCII format
to code the command and the response
messages. Application programs running on the
host PC issue commands and then await
responses from the MicroDAC. The
communications speed is selectable between
1.2 and 115.2 KBaud. Each controller on the
network is assigned a unique base address. You
can separate units from one another by as much
as 4,000 feet.
ANALOG & DIGITAL I/O
A 50 conductor ribbon cable is supplied to connect
MicroDACs to any 8,16,24, or 32 module
mounting rack. If connected to a G5 rack, any
combination of analog and digital I/O modules
may be used. OpenLine®, standard and mini
racks permit only a combination of digital modules.
MicroDACs can be networked to a PC which
runs programs that monitor the input signals and
control the outputs. In addition to simple ON/OFF
instructions, commands are included which
permit you to:
• Sample analog signals at 10 mS per input
• Flag values above or below prescribed levels
• Capture min/max values
• Calculate the average input signal levels
• Provide linearized thermocouple and
RTD temperature values
• Determine the width of input pulses
• Count pulses at frequencies up to 1000 Hz
• Detect rising or falling edges
• Latch momentary input events
• Set the level of analog outputs
• Provide delayed-on or delayed-off outputs
EMBEDDED CONTROL
PROGRAMS
By specifying MicroDAC(s) with the optional
64KB of flash memory, you can develop and
download C language programs to any of the
networked controllers.
Even while an Embedded Control Program (ECP)
is running on MicroDAC, any Optomux™
command it receives from the host will be
processed as usual, which allows you to delegate
some or all of the control and data acquisition
responsibility from the host PC. This reduces
communications time and improves system
response.
For embedded or stand-alone applications,
downloaded ECP routines can be initiated on
power-up. Where redundant control or process
shutdown procedures are vital, ECP initiation can
be tied to the communications watchdog timer. In
the event the host computer goes off line, the ECP
automatically begins executing.
Libraries and the appropriate download utility are
included with the ECP Programmers Manual.
SOFTWARE
Software drivers are available which simplify the
task of interfacing host programs written in Visual
Basic or C. Sample programs, set-up and debug
utilities are included on the disk with the drivers.
Interface drivers for most third party software
packages are available through their distributors.
Our MicroDAC DDE Server dramatically
simplifies data sharing between MicroDACs and
Windows applications, such as Microsoft Excel
(see Optomux Software). Our DLL will assist you
in building custom Windows Man-Machine
Interfaces or control programs using Visual Basic,
Visual C/C++, or Borland compilers.
OTHER FEATURES/OPTIONS
The RS-232 serial port provides a connection for
remote RS-232 devices. You can use this port to
read information from input devices such as bar
code readers or keyboards or to write information
to output devices such as operator interfaces,
intelligent displays or printers.
The optional real time clock permits ECP routines
to be executed based on date or time of day. It
also allows data that is collected to be time
stamped and stored in battery backed RAM
memory.
System 50
29
Grayhill, Inc. • 561 Hillgrove Avenue • LaGrange, Illinois 60525-5997 • USA • Phone: 708-354-1040 • Fax: 708-354-2820 • www.grayhill.com