Pulsar TC-10B, Руководство пользователя

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help–General help, lists all commands briefly.
help set–Discusses all the setting commands
in more detail.
help retries–Gives examples and specific
usage for the set retries command.
All commands are summarized in Tables 16-5
through 16-13 (see "Checkback Command Quick
Reference" on the following page).
16.5.6 Distant Checkback
Communications
Universal Checkback Modules can communicate
with any others on the same network. Any
command that you can execute at the module you
are connected to can also be redirected to some
distant module. For example, if you are at remote
#2 and you want to change remote #1's major
alarm output state to "closed" on alarm, you could
type the following and press the ENTER key:
set major = closed > 1
The redirection character (>) tells the local
checkback module to send this command on to
remote #1, rather than execute this command
locally. The master and all remote modules have
the same communication privileges. That is, any
module can redirect a command to any other
module.
To communicate with a distant module, you must
first log onto that module. This is a security
measure designed to limit access. A checkback
module's distant logon password is always the
same as its local logon password, although every
checkback module can have a unique password.
For example, let's say you are at remote #1. You
want to log onto the master and its password is
"dilbert". You type: logon dilbert > 0 and press
the ENTER key.
Note that this appears on the screen as: logon
******>0
Remember that address "0" is reserved for the
master checkback module.
The distant logon remains in effect until you do
one of the following:
• Log off the distant module
• Log off locally
• Do not communicate with the remote
module for 15 minutes
If you want, you can log onto all checkback
modules in the network at once. To remain logged
on, however, you have to talk to each module
before it times out.
16.5.6.1 Limitations and Concerns
1. The data rate is slow, 60 bits per second. A
long command like get settings from a distant
checkback module takes 30 seconds or more
to complete, depending on the quality of the
communication channel.
2. The system is only intended to support one
module communicating at a time. If multiple
modules attempt to talk, commands may fail,
although any data that gets through will be
accurate.
3. Changing a distant module's address is
permitted, but avoid assigning it an address
that is already in use - or you will not be able
to talk to either module at that address until
you can locally change one or the other's
address.
October 2003 Page 16–35
Chapter 16. Universal Checkback Module
16