Varian HS452, Инструкция по эксплуатации

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TECHNICAL INFORMATION
well as the device address by means of the T-plus
software
NOTE
The RS-485 is a 2-wire (gnd optional) half-duplex
communication link.
Communication Format
•
Physical level: both RS232 e RS485
•
8 data bit
•
no parity
•
1 stop bit
•
baud rate: 600/1200/2400/4800/9600 pro-
grammable
Communication Protocol
The communication protocol is a MASTER/SLAVE
type where:
•
Host = MASTER
•
Pump = SLAVE
The communication is performed in the following
way:
1. the host (MASTER) send a
M CRC
to
the controller (SLAVE);
2. the controller answer with an
CRC
to the host.
The
MESSAGE
is a string with the following format:
<STX>+<ADDR>+<WIN>+<COM>+<DATA>+<ETX>
+<CRC>
where:
NOTE
When a data is indicated between two quotes (‘...’)
it means that the indicated data is the correspond-
ing ASCII character.
−
<STX>
(Start of transmission) = 0x02
−
<ADDR>
(Unit address) = 0x80 (for RS 232)
<ADDR>
(Unit address) = 0x80 + device num-
ber (0 to 31) (for RS 485)
−
<WIN>
(Window) = a string of 3 numeric char-
acter indicating the window number (from ‘000’
to ‘999’); for the meaning of each window see
the relevant paragraph.
−
<COM>
(Command) = 0x30 to read the window,
0x31 to write into the window
−
<DATA>
= an alphanumeric ASCII string with
the data to be written into the window. In case
of a reading command this field is not present.
The field length is variable according to the
data type as per the following table:
DATA TYPE FIELD
LENGTH
VALID
CHARACTERS
Logic (L) 1 ‘0’ = OFF
‘1’ = ON
Numeric (N) 6 ‘-‘, ‘.’, ‘0’ . . . ‘9’ right
justified with ‘0’
Alphanumeric (A) 10 from blank to ‘_’ (ASCII)
−
<ETX>
(End of transmission) = 0x03
−
<CRC>
= XOR of all characters subsequent to
<STX>
and including the
<ETX>
terminator.
The value is hexadecimal coded and indicated
by two ASCII character.
The addressed SLAVE will respond with an
AN-
SWER
whose structure depends from the
MESSAGE
type.
When the
MESSAGE
is a reading command, the
SLAVE will respond transmitting a string with the
same structure of the
MESSAGE
.
The controller can answers with the following re-
sponse types:
TYPE LENGTH VALUE DESCRIPTION
Logic 1 byte -
After a read instruc-
tion of a logic win-
dow
Numeric 6 bytes -
After a read instruc-
tion of a numeric
window
Alpha-
numeric
10 bytes -
After a read instruc-
tion of an alphanu-
meric window
ACK 1 byte (0x6)
The command exe-
cution has been
successfully com-
pleted
NACK 1 byte (0x15)
The command exe-
cution has been
failed
Unknown
Window
1 byte (0x32)
The specified win-
dow in the com-
mand is not a valid
window
Data Type
Error
1 byte (0x33)
The data type
specified in the
command (Logic,
Numeric or Alpha-
numeric) is not ac-
corded with the
specified Window
Out of
Range
1 byte
(0x34)
The value ex-
pressed during a
write command is
out of the range
value of the speci-
fied window
Win Dis-
abled
1 byte (0x35)
The specified win-
dow is Read Only
or temporarily dis-
abled (some values
cannot be changed
while pump is run-
ning)
22 87-900-978-01(D)