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If you were writing a program in BASIC to turn on address 10
decimal (0A hexadecimal) you might form a string like this:
DSS0AON$ = CHR$(19) + "0" + "A" + CHR$(1)
You could then send DSS0AON$ to select 485DSS address 10 (0A
hex). Use similar strings for turning on the other 485DSS's.
OFF Command
This command turns off all 485DSS's on the network and lowers
the RTS output handshake line on pin 4 of the DB25 connector. The
command string consists of all non-printable ASCII characters. This
command uses two broadcast characters "DC2" (decimal 18) in the
address field. Sending this command before sending a command
that has a specific address (address characters are printable) keeps
the RS-232 device from outputting any printable characters.
NOTE: This command permits only the use of the broadcast
characters in the address field.
Command character:
Example 1: Turn off all the 485DSS's on the network.
HOST transmits:
The turn off string in BASIC might look like this:
DSSOFF$ = CHR$(19) + CHR$(18) + CHR$(18) + CHR$(4)
You could then send DSSOFF$ to turn off all 485DSS's.
ALL data and control characters are passed through the 485DSS
after it has been selected.
STATUS REQUEST Command
The Status Request command requests the status of an
individual 485DSS or the status of all 485DSS's on the network.
This command enables the Host computer to determine from each
reply message received if the RS-232 device is requesting access to
the network and if it has access to the network. By using this
command the Host has the ability to prioritize all the 485DSS's on
the network. A specific address in the address field specifies a
485DSS-0308 Manual
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104
B&B Electronics – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph +353 91 792444 – Fax +353 91 792445
EOT (decimal 4)
Xoff DC2 DC2 EOT
( 19
18
18
( 13
12
12
4 decimal)
4 hex)
11
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