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RJ-12
This describes a 6-pin connecting cable with a standardized modular (Western) connector.
RJ-45
This describes a 8-pin connecting cable with a standardized modular (Western) connector.
RS-485
RS-485 is a standard for data transmission with 5 V differential signals. The RS-485
interface uses only one pair of wires and is operated in half duplex. The connection is
multipoint-compliant; in other words, up to 32 subscribers can be connected.
Send buffer / image memory
A TIM has a send buffer and a message image memory for buffering send messages. A
fixed position is reserved in this image memory for each data message transferred to the
TIM for transmission. Each newly transferred message always overwrites the old message in
the image memory. The image memory therefore contains all data messages with their latest
content.
The entry of send messages in the send buffer can therefore take place in two ways,
according to the send buffer principle or the image memory principle.
Send buffer principle
A TIM has a send buffer for buffering send messages. If a send message is entered using
the send buffer principle, each time the message is transferred to the TIM, it is entered
completely in the send buffer. As a result, it can exist more than once in the send buffer.
When the message is transmitted, it is taken completely from the send buffer and
transmitted: transmission is according to the send buffer principle.
Setpoint
A setpoint is a selected digital or analog value that is transmitted once after the value has
been set. The entered value is recalculated when necessary. A setpoint is always
transmitted as 1 word. At the receiving end, the setpoint can either the output directly to the
process as an analog signal (for example to an external controller) or the value is made
available to the local program for further processing (setpoint for internal controller, limit
value, threshold value etc.).
Setpoint and command input are interlocked for safety reasons; in other words, a setpoint
input cannot be made at the same time as a command input. In this case, the acquisition
program recognizes an error. Neither the setpoint nor the command are transmitted.
SIM card
(Subscriber Identity Module)
The SIM card is an identification card for a subscriber of a GSM mobile wireless network.
SINAUT ST7 Station control system - System Manual
System Manual, 05/2007, C79000-G8976-C178-06
Glossary
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