Guildline 6564, Техническое руководство

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Section 3
TM6564-C-00
26 April, 2011
3-5
3.5. OPERATION FROM INTERFACE BUS
The interface circuit is designed to accept coded data sent over the bus to actuate the relays.
To operate with the bus the scanner must be set to a usable address and must be connected to
the controller using a 24 pin IEEE-488 cable (not supplied).
The scanner was set at the factory for bus address 5, while all the examples that follow
assume 24 as the address. The address can be easily changed if necessary by means of a
“DIP” switch on the interface board located under the top cover. Refer to paragraph 3.4 for
the procedure to change the bus address.
To actuate a relay the bus interface must first receive the correct address, then a three
character ASCII codes designating the relay, and then a carriage return/line feed. For
example using an HTBasic computer, the statement:
OUTPUT 724;”A01”
Would cause any relay on the CHANNEL to be cleared, and then relay number 1 to be
closed. In this example
7 is the controller IO address,
24 is the scanner address and
A01 is the code for relay 1 on the CHANNEL
Note that each actuation must be a separately addressed statement. For example, the
following is not valid:
OUTPUT 724;”A00”,”A02” —NOT VALID—
Note also that a delay of at least 200 milliseconds must occur between any two actuations to
allow the relays to complete their operation.
Programming languages such as LabVIEW
®
that do not automatically add a carriage return/
line feed at the end of the command will require a CR/LF or simply a fourth alphanumeric
character to be added to the command when addressing the scanner. The following examples
use a space as the fourth character or the CR/LF.
IBWRT "A01 “