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Device manual AS-i M4 Gateway Profibus DPV1 (AC1375, AC1376)
2012-02-23
Glossary of Terms
513
MBd
MegaBaud
Baud, abbrev.: Bd = unit for the data
transmission speed. Do not confuse baud with
"bits per second" (bps, bits/s). Baud indicates
the number of changes of state (steps, cycles)
per second over a transmission length. But it is
not defined how many bits per step are
transmitted. The name baud can be traced
back to the French inventor J. M. Baudot
whose code was used for telex machines.
1 MBd = 1024 x 1024 Bd = 1 048 576 Bd
MMI
HMI =
H
uman
M
achine
I
nterface
HMI (
→
page
Modbus
The Modbus protocol is a communication
protocol based on a
master/slave
architecture and was generated by Modicon in
1979 for communication with its PLCs. In the
industry, Modbus has become a de facto
standard.
Modbus/TCP is based on
Ethernet TCP/IP.
Modbus/TCP ports the protocol defined for the
serial interface to TCP. The
IP address
clearly identifies each device in a network.
Therefore the slave address was used to
identify one of several logical units (unit IDs) in
a physical device. To do so, the extended
IP addressing is used.
Example: 192.168.83.28.1 means unit ID 1 on
IP address 192.168.83.28.
*) Modicon passed from AEG to the group
Schneider in 1994.
MRAM
MRAM means
M
agnetoresistive
R
andom
A
ccess
M
emory. The information is stored by
means of magnetic storage elements. The
property of certain materials is used to change
their electrical resistance when exposed to
magnetic fields.
Advantages of MRAM as compared to
conventional RAM memories:
non volatile (like FRAM), but:
access time only approx. 35 ns,
unlimited number of access cycles
possible.
MSB
M
ost
S
ignificant
B
it/Byte
O
Operating system
Basic program in the device, establishes the
connection between the hardware of the
device and the user software.
OSC
OSC =
O
nline
S
upport
C
enter
Online
diagnosis system
Help system in the device
OSSD
OSSD =
O
utput
S
ignal
S
witching
D
evice
= output signal of a switching device. Here:
output signal of an AS-i safety monitor.
P
Password
In the menu [System Setup], menu item
[Password] the handling can be restricted or
enabled. When delivered, the device is in the
user mode. By entering an invalid password
(e.g. 1000) all menu items which can change
settings are blocked.
PCCD
PCCD =
P
rojected
C
TT
C
onfiguration
D
ata
Configuration data for the 7.4 and 7.5 slaves
stored in the device:
- Manufacturer ID,
- Vendor ID,
- Device ID,
- Device Group ID.
PCD
PCD =
P
rojected
C
onfiguration
D
ata
Configuration data stored in the device:
LPS and AS-i profile (IO, ID, ID1, ID2)
