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.
Содержание ENET-232 Series
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Страница 5: ...Using Help Conventions Navigating Help Searching Help Printing Help File Topics ...
Страница 17: ...How to Use this Help File To use this help file refer to the following flow chart and the appropriate topics ...
Страница 21: ...Serial Hardware Overview PCI Kits PXI Kits USB Kits ENET Kits ExpressCard Kits PCMCIA Kits ...
Страница 24: ...PCI 485I RS 485 two port isolated RS 485 four port isolated ...
Страница 27: ...PXI 8423 RS 485 two port isolated RS 485 four port isolated ...
Страница 63: ...Save Pending Changes To save your changes to this item click Save ...
Страница 65: ...Restore Defaults To reset the fields to their default values at any time click the Defaults button ...
Страница 98: ...0 LPVOID l_SerialInterface sizeof l_SerialInterface LPDWORD l_ByteCount NULL ...
Страница 127: ...2 PORT LEDs USB Serial Hardware LEDs ...
Страница 139: ...Connecting the Cables to a Four Port PXI Serial Board ...
Страница 141: ...67 58 50 41 33 24 16 7 TXD 9 RI 9 ...
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Страница 181: ...How many serial ports can I have on my machine You can have up to 256 serial ports ...
Страница 189: ...nslookup hostname If you still cannot communicate with your device contact National Instruments ...
Страница 201: ...Glossary Prefixes Symbols A B C D E F G H I K L M P R S T U V ...
Страница 203: ...Symbols degrees ohms percent ...
Страница 204: ...A A amperes ANSI American National Standards Institute ...
Страница 205: ...B b bits B bytes baud bits per second bps bits per second ...
Страница 206: ...C C Celsius COM Computer Output Microform used in reference to a communication port CTS clear to send ...
Страница 208: ...E EIA Electronic Industries Association EMI electromagnetic interference ENET Ethernet ...
Страница 209: ...F FCC Federal Communications Commission FIFO First In First Out ft feet ...
Страница 210: ...G G ground ...
Страница 211: ...H HSI handshake input HSO handshake output Hz Hertz ...
Страница 213: ...K Kbaud kilobits per second ...
Страница 214: ...L LED light emitting diode ...
Страница 215: ...M m meters MB megabyte ...
Страница 216: ...P PC personal computer PCI Peripheral Components Interconnect ...
Страница 218: ...S s seconds SCSI Small Computer Systems Interface ...
Страница 220: ...U UART Universal Asynchronous Receiver Transmitter ...
Страница 221: ...V V volts VDC volts direct current VXI VME eXtensions for Instrumentation ...
Страница 222: ...Important Information Warranty Copyright Trademarks Patents Warning Regarding Use of NI Products Compliance ...