B&R Industries Automation PC 620, Руководство пользователя

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Appendix A • Glossary
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483 Automation PC 620 User's Manual V 1.90
RTS
An abbreviation for »Request To Send« A signal used in serial data transfer for requesting send
permission. For example, it is sent from a computer to the modem connected to it. The RTS
signal is assigned to pin 4 according to hardware specifications of the RS-232-C standard.
RXD
An abbreviation for »Receive (RX) Data« A line for the transfer of serial data received from one
device to another - e.g. from a modem to a computer. For connections complying with the RS-
232-C standard, the RXD is connected to pin 3 of the plug.
SDRAM
An abbreviation for »Synchronous Dynamic Random Access Memory« A construction of
dynamic semiconductor components (DRAM), which can operate with higher clock rates than
conventional DRAM switching circuits. This is made possible using block access. For each
access, the DRAM determines the next memory addresses to be accessed.
SFC
Sequential function chart >; Used for graphic representation of sequential control, graphic input
language for PLCs.
Slot PLC
PC insert card that has full PLC functionality. On the PC, it is coupled via a DPR with the process
using a fieldbus connection. It is programmed externally or using the host PC.
SRAM
An abbreviation for »Static Random Access Memory« A semiconductor memory (RAM) made
up of certain logic circuits (flip-flop), which only keeps stored information while the operating
voltage is active. In computers, static RAM is generally only used for the cache memory.
SUXGA
Abbreviation for Super Ultra Extended Graphics Array; Generally a screen resolution of 2048 ×
1536 pixels (4:3). An alternative name is QXGA (Quad Extended Graphics Array), which is 4x
the pixel resolution of XGA.
SVGA
Abbreviation for »Super Video Graphics Array«; Graphics standard with a resolution of at least
800×600 pixels and at least 256 colors.
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