a2 – a0
Unit address for slave
● Individual address of the unit ["001";"255"]
● Group address "9xx" for all identical units (no response)
● Global address "000" for all units on the bus (no response)
*
Action according to telegram description
n2 – n0
Pfeiffer Vacuum parameter numbers
I1 – I0
Data length dn to d0
dn – d0
Data in the respective data type
(see chapter “Data types”, page 36)
.
c2 – c0
Checksum (sum of ASCII values of cells a2 to d0) modulo 256
C
R
carriage return (ASCII 13)
6.3.2 Telegram description
Data query
-->
?
a2
a1
a0
0
0
n2
n1
n0
0
2
=
?
c2
c1
c0
c
R
Control command
-->
!
a2
a1
a0
1
0
n2
n1
n0
l1
l0
dn
...
d0
c2
c1
c0
c
R
Data response / Control command understood
-->
a2
a1
a0
1
0
n2
n1
n0
l1
l0
dn
...
d0
c2
c1
c0
c
R
Error message
-->
a2
a1
a0
1
0
n2
n1
n0
0
6
N
O
_
D
E
F
c2
c1
c0
c
R
_
R
A
N
G
E
_
L
O
G
I
C
NO_DEF
Parameter number n2–n0 no longer exists
_RANGE
Data dn–d0 outside the permissible range
_LOGIC
Logical access error
6.3.3 Telegram example 1
Data query
Current rotation speed (parameter
[P:309]
, device address slave: "123")
-->
?
1
2
3
0
0
3
0
9
0
2
=
?
1
1
2
c
R
ASCII
49
50
51
48
48
51
48
57
48
50
61
63
49
49
50
13
Data response: 633 Hz
Current rotation speed (parameter
[P:309]
, device address Slave: "123")
-->
1
2
3
1
0
3
0
9
0
6
0
0
0
6
3
3
0
3
7
c
R
ASCII
49
50
51
49
48
51
48
57
48
54
48
48
48
54
51
51
48
51
55
13
6.3.4 Telegram example 2
Control command
Switch on the pumping station (parameter
[P:010]
, device address Slave: "042"
-->
!
0
4
2
1
0
0
1
0
0
6
1
1
1
1
1
1
0
2
0
c
R
ASCII
48
52
50
49
48
48
49
48
48
54
49
49
49
49
49
49
48
50
48
13
Control command understood
Switch on the pumping station (parameter
[P:010]
, device address Slave: "042"
Interfaces
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