PD
3940 P-NET to RS232 INTERFACE
FEATURES
* P-NET Fieldbus Communication, European standard EN 50170, Vol. 1.
* RS232 port (9 pin male).
* Integrates RS232 devices with P-NET
* Fully configurable via P-NET.
* Baud rates from 300 to 76,800.
* Standard RS232 handshake signals.
* Galvanically isolated com. ports.
* Full duplex communication.
* Dynamic buffer size.
* IP53 mounting box.
* Panel mount facilities.
* EMC approved (89/336/EEC).
APPLICATION
The PD 3940 is a communication module, providing an interface from the P-NET
fieldbus to RS232 devices, such as printers, card-readers, barcode readers and
other equipment not having built-in fieldbus facilities for P-NET. This enables
such devices to be integrated into a P-NET fieldbus system. It can be used in
conjunction with the varied collection of distributed P-NET input/output and
control modules, which provide digital, analog, flow and weighing facilities.
Application examples:
- Printer interface, for printout of
tickets, alarms and reports.
- Card-reader interface, for entrance
control.
- Bar-code reader interface, for
production control to track the flow of materials.
SYSTEM DESCRIPTION
The PD 3940 P-NET to RS232 communication module provides an interface between
the P-NET fieldbus and any RS232 device. It is connected to P-NET in the same
way as any other node, and has a built in RS232 9-pin male connector. The PD
3940 is mounted in an IP53 polycarbonate mounting box. Four PG11 cable glands
are provided, for connection of the P-NET fieldbus and power supply cables.
The PD 3940 is a P-NET slave, which has 2 channels, the Service channel (channel
0) and the Communication channel (channel 1).
The service channel, which is mandatory in all P-NET modules, holds among other
things, general information about the module, such as ID, serial no., P-NET node
no. and error status of the complete module. The Communication channel holds all
data applicable to the RS232 port set up (baud rate, parity, handshake etc),
input/output data buffers and error status of the channel. Errors reported
include configuration errors, communication errors and module errors.
It is possible to set a Simulation
enable bit, for test purposes. If Simulation is selected, direct access to the
input buffer is allowed, and data from the RS232 port will be ignored.
The Reservation facility allows a master to reserve the module for a certain
period of time. In a multi-master network, this feature can prevent other
masters from accidentally writing data in the output buffer while, e.g. writing
a report.
If the Dynamic buffer enable bit is selected, a read access to the input buffer
will return the actual number of bytes, which have been received at the time of
the read operation. This feature may, for example, be useful when the packages
of data recieved on the RS232 port are not of a fixed length.
Data that are to be sent (e.g. to a printer) on RS232 must be stored in the
Output buffer in the communication channel. Data received (e.g. from a barcode
reader) are stored in the Input buffer, from where it can be read via P-NET.
SPECIFICATIONS (all specifications apply under the stated EMI
conditions):
Power supply:
Scale Drawing (in mm)
Voltage:
24V DC +/- 15 %
Consumption:
1.2 W
Ambient Temperature:
Operation:
-25 to +70°C
Storage:
-40 to +85°C
Sealing:
IP53
Enclosure:
Polycarbonate mounting box
Weight:
0.500 kg
RS232 Communication Interface:
Baudrates:
300 to 76,800
Parity:
None, even, odd, mark, space
Output
buffer:
Buffer[10] of STRING[255]
Input
buffer:
Buffer[10] of STRING[255]
PD 3940 is approved in compliance
with the EMC-directive no 89/336/EEC. Test limits are determined by the generic
standards EN 50081-1 for emission and EN 50082-2 for immunity.PD 3940 is
approved in compliance with the IEC 68-2-6 Test Fc standard for vibration.
|