Digi XBee-PRO XM-M92-2P Series, Руководство по эксплуатации продукта, Страница: 12 / 23

XBee
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PRO® 900HP RS
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232/RS
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485/USB RF Modem
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Product Manual
© 2013 Digi International Inc. 12
Sa m ple W ir e le ss Con ne ct ion : D TE < - - > D CE D CE < - - > D CE
Figure 2
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04. Typical wireless link between DTE and DCE devices
2 .2 . RS- 4 8 5 ( 2 - w ir e ) Ope r a t ion
Note that with the RS-485 variant of the 900HP RF Modem, the RF Modem is defaulted with the D7
command (AT parameter) to 7. This parameter controls the TX enable signal and allows the
modem to output any data in the DO buffer to the host device for the RS-485 interface. In the
event that the parameter is accidentally changed, which would halt RS-485 communication, a USB
mini cable should be plugged into the modem to reconfigure it. You can reconfigure by using Digi’s
X-CTU.
With the USB plugged in:
1. Open X-CTU and select the Com port of the USB.
2. Select the Terminal tab and type '+++'. The system will respond with 'OK'.
3. Type “ATD77” then <Enter>, and the system will respond with 'OK'. Type “ATWR” then
<Enter>, and the system will respond with “OK”.
4. Type “ATCN” then <Enter> to exit command mode, and the system will respond with “OK”.
5. Unplug the USB and return to the existing RS-485 interface. The 900HP RF Modem is now
ready to communicate in RS-485 model.