Acces ICOM-2S, User Manual

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ICOM-2S Manual
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Manual MICOM-2S.Eb
Auto and Manual Transceiver Control
RS485 communications requires the transmitter driver to be enabled and disabled as needed, to allow
all cards to share the communications line. The ICOM-2S card has two methods to control the driver:
automatic (Auto) and request to send (RTS) control.
With automatic control, the driver is enabled when data is ready to be transmitted. The driver remains
enabled for the transmission time of one character after data transfer is complete. The ICOM-2S
automatically adjusts it's timing to the baud rate of the data. When operating with Windows programs,
you must use the Auto mode.
With RTS control, your software must set the RTS bit to a logic 1 to enable the driver and logic 0 to
disable the driver.
Led Monitors
Two LED indicators are provided on the ICOM-2S card. The LEDs blink to indicate activity on the
transmitting and receiving lines and are useful for problem diagnosis. The blinking is more visible at
slower speeds as high speed communication blinks the LEDs too fast for the eye to follow.
Communication Modes
Model ICOM-2S supports Simplex, Half-Duplex, and Full-Duplex communications in a variety of 2
and 4-wire cable connections. Simplex is the simplest form of communications with transmissions
occurring only in one direction. Half-Duplex allows traffic to travel in both directions, but only one
direction at a time. In Full-Duplex mode data travels in both directions at the same time. RS485
communication only supports Half-Duplex because the same pair of signal lines are used for
transmitting and receiving.
CE Marking
If your card is CE-marked unit, it meets requirements of EN50081-1:1992 (Emissions),
EN50082-1:1992 (Immunity), and EN60950:1992 (Safety).