Intermec Janus 2020 User Manual page 197

6
BC
NF
Networking the Reader
PC Standard Protocol PC Standard handles data transfer on a character-by-
character basis or by either filling a receive buffer or transmitting a buffer of
data. This protocol is designed to be compatible with the standard PC BIOS
functions. The one exception is that the PC Standard protocol can buffer data
that is received to avoid losing characters if a program has not checked for data
recently.
Point-to-Point Protocol Point-to-Point is an unsolicited protocol in which the
reader transmits data whenever it has something to transmit. The data is
followed by a CR LF as the EOM characters. The reader is always in a receiving
state and does not wait for select commands. This protocol does not perform
any error checking or acknowledgment handshaking.
Point-to-Point protocol is typically used to connect the reader to a CRT
terminal or host computer. Since Point-to-Point is an unsolicited protocol, you
can initiate the transmit command from the reader or the host.
Polling Mode D Protocol Polling Mode D requires the host computer to ask the
reader for data it might have (polling) and to request to send data to the reader
(selecting). PC-IRL uses this protocol.
RF Protocol RF Protocol is used in radio frequency (RF) networks only. For
details, see your JANUS RF documentation.
User-Defined Protocol User-Defined is a powerful protocol because you can
configure the protocol to your own requirements. For example, you can
configure User-Defined to act like a Point-to-Point protocol, except that it
requires an LRC and an acknowledgment from the receiver. You can also
define the communications characters such as SOM, POL, or SEL, or disable
these characters by setting them to null.
You can also use User-Defined protocol to define User-Defined Multi-Drop
protocol. In User-Defined Multi-Drop, you must set the POL and SEL protocol
characters in a predetermined combination. For help, see "POL and SEL
Combinations for Multi-Drop Protocol" in Appendix C.
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