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TECHNICAL INFORMATION
81 87-900-986-01 (
C
)
The following parameters can be changed:
BYTES
MEANING
1
Speed threshold
2-5
Run up time in seconds
(long coded in 4 bytes)
6
Deat time
(0 = NO 1 = YES)
7
Reserved
8
Soft Start mode
(0 = YES 1 = NO)
9
CRC
When the
Request
is "I" (Status readings), the
Answer
will contain a string of 2 characters with the following
parameters:
BYTES
MEANING
1
MSB LSB
- - X X X X X X
0 = STOP
1 = WAITING INTERLOCK
2 = STARTING
3 = NORMAL OPERATION
4, 5 = HIGH LOAD
6 = FAILURE
7 = APPROACHING LOW SPEED
R2 status 0 = OFF 1 = ON
R1 status 0 = OFF 1 = ON
2
CRC
When the
Request
is "J" (Numerical readings), the
Answer
will contain a string of 5 characters with the
following parameters:
BYTES
MEANING
1
Current (0-255 scaled)
2
Voltage (0-255 scaled)
3
Rotational speed KRPM
4
Pump temperature °C
(0-254 temperature reading, 255 = fail)
5
CRC
When the
Request
is "K" (Counters readings), the
Answer
will contain a string of 11 characters with the
following parameters:
BYTES
MEANING
1-4
Cycle time
5-8
Pump life
9-10
Cycle number
11
CRC
On request a sample program in QBasic language is
available by Varian.
Window Protocol
Description
Communication Format
•
8 data bit
•
no parity
•
1 stop bit
•
baud rate: 600/1200/2400/4800/9600 programmable
Communication Protocol
The communication protocol is a MASTER/SLAVE type
where:
•
Host = MASTER
•
Controller = 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 corresponding
ASCII character.
−
<STX>
(Start of transmission) = 0x02
−
<ADDR>
(Unit address) = 0x80 (for RS 232)
<ADDR>
(Unit address) = 0x80 + device number (0
to 31) (for RS 485)
−
<WIN>
(Window) = a string of 3 numeric character
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.