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Device Manual AS-i IO-Link-Gateway (AC5225) Firmware V1.16
2017-11-20
Glossary of Terms
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Ethernet
Ethernet is a widely used, manufacturer-independent technology which enables data transmission in
the network at a speed of 10...10 000 million bits per second (Mbps). Ethernet belongs to the family of
so-called "optimum data transmission" on a non exclusive transmission medium. The concept was
developed in 1972 and specified as IEEE 802.3 in 1985.
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Explicit Messaging
Acyclic data exchange between
→ I/O scanner and → I/O adapter based on the TCP/IP
communication protocol.
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F
FC
FC = flat cable. The yellow or black AS-i cable is meant.
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FE – functional earth
F
unctional
e
arth is a reference potential which is not connected to protective earth or only connected
when special measures are taken. The functional earth serves as equalisation of potential for an
ungrounded installation (e.g.
→SELV).
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Fieldbus
A
→bus for industrial applications: mechanically extremely robust and excellent data protection.
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Firmware
System software, basic program in the device, virtually the
→runtime system.
The firmware establishes the connection between the hardware of the device and the application
program. The firmware is provided by the manufacturer of the controller as a part of the system and
cannot be changed by the user.
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Flash memory
Flash ROM (or flash EPROM or flash memory) combines the advantages of semiconductor memory
and hard disks. Similar to a hard disk, the data are however written and deleted blockwise in data
blocks up to 64, 128, 256, 1024, ... bytes at the same time.
Advantages of flash memories
The stored data are maintained even if there is no supply voltage.
Due to the absence of moving parts, flash is noiseless and insensitive to shocks and magnetic
fields.
Disadvantages of flash memories
A storage cell can tolerate a limited number of write and delete processes:
• Multi-level cells: typ. 10 000 cycles
• Single level cells: typ. 100 000 cycles
Given that a write process writes memory blocks of between 16 and 128 Kbytes at the same time,
memory cells which require no change are used as well.
Summary of Contents for AC5225
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