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Why isn't the Auto232 transceiver mode on my
USB-232 working?
The Auto232 mode of operation allows you to connect to either a RS-232
DTE or DCE device using either a null-modem or straight-through cable.
The USB-232 port will automatically switch approximately every 250 ms
between DTE and DCE operating modes until at least one RS-232
receiver line (RX, CTS, DSR, RI, or DCD) has a valid voltage. Auto232 is
available on the USB-232/2 and USB-232/4, and is not available on the
USB-232 (single port).
Not all devices and applications can take advantage of this feature:
Some devices can generate valid voltages on receive lines for both
modes, even though the device itself is only DTE or DCE. Thus,
these devices may not operate correctly when using Auto232
mode.
Some applications immediately start communicating after a COM
port is open, thus not allowing enough time for the proper
operating mode to be selected.
Some cabling schemes short RI, DCD, and DSR together. While
this does not present a problem in DTE mode, these signals are
driven when in DCE mode. Thus, by shorting the signals together,
the outputs will be double (or triple) driven which may cause signal
noise or other artifacts. Use a straight-through cable instead.
If problems with Auto232 can not be resolved, set the USB-232 to the
correct mode (DTE or DCE) for your device and application. By default,
the USB-232 ports are set to DTE mode.
Summary of Contents for ENET-232 Series
Page 1: ......
Page 5: ...Using Help Conventions Navigating Help Searching Help Printing Help File Topics ...
Page 21: ...Serial Hardware Overview PCI Kits PXI Kits USB Kits ENET Kits ExpressCard Kits PCMCIA Kits ...
Page 24: ...PCI 485I RS 485 two port isolated RS 485 four port isolated ...
Page 27: ...PXI 8423 RS 485 two port isolated RS 485 four port isolated ...
Page 63: ...Save Pending Changes To save your changes to this item click Save ...
Page 98: ...0 LPVOID l_SerialInterface sizeof l_SerialInterface LPDWORD l_ByteCount NULL ...
Page 127: ...2 PORT LEDs USB Serial Hardware LEDs ...
Page 139: ...Connecting the Cables to a Four Port PXI Serial Board ...
Page 141: ...67 58 50 41 33 24 16 7 TXD 9 RI 9 ...
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Page 181: ...How many serial ports can I have on my machine You can have up to 256 serial ports ...
Page 201: ...Glossary Prefixes Symbols A B C D E F G H I K L M P R S T U V ...
Page 203: ...Symbols degrees ohms percent ...
Page 204: ...A A amperes ANSI American National Standards Institute ...
Page 205: ...B b bits B bytes baud bits per second bps bits per second ...
Page 208: ...E EIA Electronic Industries Association EMI electromagnetic interference ENET Ethernet ...
Page 209: ...F FCC Federal Communications Commission FIFO First In First Out ft feet ...
Page 210: ...G G ground ...
Page 211: ...H HSI handshake input HSO handshake output Hz Hertz ...
Page 213: ...K Kbaud kilobits per second ...
Page 214: ...L LED light emitting diode ...
Page 215: ...M m meters MB megabyte ...
Page 216: ...P PC personal computer PCI Peripheral Components Interconnect ...
Page 218: ...S s seconds SCSI Small Computer Systems Interface ...
Page 220: ...U UART Universal Asynchronous Receiver Transmitter ...
Page 221: ...V V volts VDC volts direct current VXI VME eXtensions for Instrumentation ...