EM1500 User’s Manual
65
Packetizing
This is where you specify when to send data packets to the network. Since packetiza-
tion options are an extension to the standard protocol (RFC2217), it is necessary to
check the 'Rabbit extensions' option.
The available modes are:
•
None
. No packetizing is required, e.g., for a purely stream-based application.
•
Idle
. Uses idle time (i.e., no data being sent or received for a specified time interval) to
delimit one packet from the next. Idle packetization requires specifying two timing
parameters (see below). Packet length should not exceed the size of the internal buffer.
•
String Send/Cut
. Packet terminated by a fixed character string. With this mode, there is
no length limit on the packet.
•
9th bit
. Unlike “String” mode, which recognizes the end of packet, 9th bit mode looks
for the start of the packet. A packet is started by a 9th bit low. This is not compatible with
normal parity checking—any parity setting in the “Serial” tab is ignored.
Idle time units
Units in which following timeouts are set. The units may be ms (milliseconds), byte
(character times), or bit (bit times).
Available when “Idle” is chosen as the packetizing option.
Rx idle time
Specifies minimum time that serial port receiver must be idle to indicate end-of-
packet and to cause packet to be sent to network. Note that the value entered here is
rounded up to the nearest multiple of 1/32768 seconds (i.e., about 30 µs).
Available when “Idle” is chosen as the packetizing option.
Tx idle time
Minimum time that serial port transmitter is idle before sending new packet to serial
port. This value is rounded up to a multiple of 1/2048 seconds (i.e., about 488 µs).
Available when “Idle” is chosen as the packetizing option.
Summary of Contents for EM1500
Page 14: ...10 www rabbit com Introduction...
Page 22: ...18 www rabbit com Getting Started...
Page 76: ...72 www rabbit com EM1500 Configuration...
Page 90: ...86 www rabbit com EM1500 Specifications...
Page 104: ...100 www rabbit com Serial and TCP Protocols...
Page 118: ...114 www rabbit com EM1500 FAQ...