Sabio 2010D, Руководство по эксплуатации

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Serial Communications Page 7-8
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Multi-drop Mode
Though the
2010D '
s serial RS-232 ports do
not normally support multi-drop operation,
with external hardware, they can be made
to enable the transmitter only when a
the command with
2010D '
s address is
recognized. If multi-drop mode is
selected, the
2010D
will activate the DTR
line when responding to a command with the
proper address. This, in turn, would
activate a solid-state relay that connects
the
2010D '
s transmit line. Normally, the
DTR line will remain low, leaving the
transmitter disconnected.
Return Error Code
Though not a standard part of the ML
protocol, if error codes are enabled, they
can provide an invaluable diagnostic tool
for
troubleshooting communications
problems. When enabled, a two digit
numeric code, terminated by a <CR>
character, will follow the <NAK>.
A
listing of possible error codes is
provided on page 20.
Protocol
The Model
2010D
currently supports three
command protocols: Monitor Labs (ML), Dot
Command
and Modbus. Others may be
supported in the future or upon request -
please contact Sabio for details. When a
protocol is selected, all other options
will be pre-set to the standard settings
for that protocol.
Error Checking
If the ML protocol is selected, no data
verification will be selected by default,
however it is possible to select data
verification for the ML protocol, even
though it is not a standard feature of the
protocol.
The section entitled "Data
Verification Field" on page 7-16
provides more detail on these data
verification methods.
Command Start
The start-of-command character. The "@"
symbol is the default for the ML protocol.