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User Guide
Landmark Technic
Signal Processor
B1.5 System Communications Timing Data
Command response time
This is the time taken between the end of the last character of a command
and the beginning of the first character of the reply. This time is independent
of the selected baud rate.
All commands are serviced within 20ms.
Command reply time
This is the time taken by the LM Technic reply. It is directly related to the
selected baud rate and the number of characters in the reply.
NOTE
Use of the IFO command, which will involve long replies, will disrupt
internal timing and affect time function processing.
Inter-command timing
This is the time between the end of the last character of a command received
by the LM Technic and the end of the last character of its response i.e. the
period when the LM Technic is unable to take a command because it is still
processing a previous one.
This is the command response time + command reply time.
For RS232C at 9600 baud, assuming a reply of 20 characters maximum, the
inter-command time is 41ms.
Cable Lengths
The maximum cable lengths are, to a great extent, dependent on baud rate
and cable type. Generally a lower baud rate will give reliable communications
over a longer length of a given cable type.
RS232C
9600 baud, 50m (EIA RS232C standard)
