Connect Tech Blue Heat/Net User’s Manual
Revision 0.13
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Serial Port LEDs
The serial ports LEDs (two, four or eight, depending on your model) indicate serial activity for
each port.
•
A flashing LED indicates that the port in question is receiving or transmitting data.
•
BN001-004 models: If the LED is on, there is an RS-232 connection detected on the
RS-232 serial port.
Connecting Serial Devices
RS-232 Connections:
Typical RS-232 null modem connection
This is the typical way to connect to DTE type devices, such as the Blue Heat/Net. It is used
when hardware RTS-to-CTS flow control is required. The cable required is called a cross-over
or null modem cable, and is readily available at any electronics retailer/distributor.
Figure 2: Typical RS-232 null modem connection
Basic 3 wire RS-232 null modem connection:
Used to connect to DTE type devices like the Blue Heat/Net, this connection is used when
hardware RTS-to-CTS flow control is NOT required. The cable is called a cross-over cable, and
is readily available at any electronics retailer/distributor.
Figure 3: Basic 3-wire RS-232 null modem connection.
