Anaheim Automation DPD75601 Скачать руководство пользователя

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July 2004

Section 3: Controller Functions

Methods of Communication

There are two methods for sending commands to the DPD75601. One is to directly talk to the DPD75601
by using Direct Talk Mode. This is usually used with a computer or PLC (Programmable Logic Controller),
where the computer or PLC gives the DPD75601 serial commands to off-load its processor. For example:
A PLC can utilize its outputs to toggle the DPD75601’s inputs and gain control of variable speeds, variable
programs, variable distances, etc. Simply using the DPD75601 as the intelligent pulse generator, a PLC
can remove some of the tasks that were not meant for ladder logic or any PLC processing time.

The second way to give commands to the DPD75601 is to use the software program SMC60WIN to either
manually control, or to write and send programs. This method is used when the DPD75601 is the main
controller. For example: A DPD75601 can replace simple motion control and replace I/O functional when
minimal quantities of I/O are required to control specific machinery. Simple motion profiles that can operate
with 6 or less inputs and 8 or less outputs can utilize a DPD75601 controller.

Baud Rate

A term used frequently in serial data communications, a “baud” is defined as the reciprocal of the shortest
pulse duration in a data word signal, including start, stop, and parity bits. This is often taken to mean the
same as “bits per second”, a term that expresses only the number of “data” bits per second. Very often,
the parity bit is included as an information or data bit. The DPD75601 accepts a baud rate of 38400 only

The DPD75601 accepts a baud rate of 38400 only

RS232 Protocol - SW1 in RS232 position

The DPD75601 is a DCE device, therefore it will transmit on pin 2 and receive on pin3 of the DB9 RS-232
connector . The RS232 serial communication mode is single ended. This means that for each signal there
is one wire, and a common ground reference used by all the signals. The DPD75601 does not use
handshaking, thus the CTS and RTS lines are internally connected, and the CD, DTR and DSR lines are
internally connected inside the DPD75601. The signal line maintains levels of +5VDC to +15VDC and -
5VDC to -15VDC. For a valid logic level in the controller, the voltage must be at least +/-3 volts. RS232
works at distances of up to 50 feet maximum. RS232 is susceptible to electrical noise, and should not

RS232 is susceptible to electrical noise, and should not

be used in noisy areas. Always use the shortest cable connection possible. NOTE: Keep controller

be used in noisy areas. Always use the shortest cable connection possible. NOTE: Keep controller
wiring separated from motor cable/wiring.

wiring separated from motor cable/wiring.

RS485 Protocol - SW1 in RS485 position

The RS485 protocol mode is as follows; On board receivers will remain in active mode indefinitely.
Transmitters must be turned off when the unit is not sending data, to prevent the line from sending and
receiving data at the same time. Therefore when the PC is transmitting data its driver will be turned on and
each of the units connected will have their drivers off. If they are requested to send data back to the PC,
the selected unit will turn it’s driver on to send the data and then turn it off after it has completed transmission.
Note: The above protocol is done internally between the converter and the DPD75601. The RS485 method
of communication allows increased noise immunity and increased communication distance of up to 4000
feet without repeaters. RS485 repeaters allow an additional 4000 feet per repeater. The DPD75601 is
designed for two wire configuration. The 2 wire configuration makes use of the tristate capabilities of
RS485 to allow a single pair of wires to share transmit and receive signals for half duplex communications.
This “two wire” configuration (note that an additional ground conductor must be used) reduces cabling
cost. NOTE: Keep control wiring separated from motor cable/wiring.

NOTE: Keep control wiring separated from motor cable/wiring.