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4 Configuring the Serial Port Settings iPocket 232 User Guide
23-CML000293 iPocket232 Inc. 26
The flow control options are described Table 4.3 .
Table 4.3: Flow Control Options for Port Setting Parameter
Option Description
None
h/w
(rts/cts)
s/w
(xon/xoff)
Default
No flow control enabled. Data may be lost due to overflow during
speed communication.
Hardware handshaking uses the RTS/CTS (Request To Send/Clear
to Send) lines for flow control on the COM port. Hardware
handshaking works by altering voltage levels on these lines. When
the remote end is ready to receive data, it asserts the CTS signal to
tell the iPocket
232 to start transferring data. If the remote end is
unable to accept the data as fast as it is received from the
iPocket
232 , the remote end negates CTS, and the iPocket 232
suspends data transfer. When the remote end is ready for more data,
it asserts CTS again.
When the iPocket
232 is ready to receive data, it asserts the RTS
signal. If the iPocket 232 cannot accept data as quickly as the device
is passing data, it negates RTS. The iPocket 232 asserts RTS again
when it is ready to resume receiving data. This setting can be used
for the majority of installations.
Software handshaking requires that XON/XOFF characters are
asserted and obeyed on the COM port. XON is used by either the
iPocket
232 or the remote host to signal the other end to start
sending data. XOFF can also be used by either the iPocket 232 or
the remote host to signal the other to stop sending data.
N
OTE
:
XON/XOFF characters included in a data transmission are interpreted as flow
control characters and will cause transmission problems. This option is not
recommended for binary data transmission.
To set or change the
Port Setting
:
1
Choose
Serial Port
from the Device Settings menu.
2
Choose
Port Setting
from the Serial Port Settings sub-menu.