INFICON HPG400-SP ATM to High-Vacuum Gauge (Profibus) - Manual (Page 10)

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tira36e1-a (0310) BPG/HPG400 v1.cp
The output data (transmitted by the master) consist of 8 bytes of the parameter
channel or, if there is no parameter channel in the standard telegram, of 0 bytes.
Byte
1 2 3 4 5 6 7 8
Parameter channel
PKE IND res. PWE
The structure of the parameter channel is described in the table below.
The parameter channel (called PKW Interface hereinafter) consists of 8 bytes.
Octets
1 2 3 4 5 6 7 8
PKE IND res. PWE
The PKW Interface allows reading and writing of slave parameters with a maximum
data length of 4 bytes. Strings cannot be read.
The slave generates exactly one response per instruction transmitted by the
master. The instruction and response cannot be blocked. This means that exactly
one instruction per output telegram can be transmitted to the slave and that exactly
one response per input telegram can be transmitted to the master. 4 bytes of actual
data can thus be transmitted at a time.
The instruction and response are represented in the first two bytes (PKE) of the
parameter channel:
Bit position
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
AK res. Slot
Where: Bits Meaning
15 … 12 AK Instruction/response signature
11 … 8 Reserved
7 … 0 Define the slot from which data are read or onto which a
value is to be written
In Master ⇒ Slave communication, the AK field contains the instruction signature of
the master.
In Slave
⇒ Master communication, the AK field contains the instruction signature of
the slave.
AK Function
Master ⇒ Slave
(Instruction signature)
AK
normal
Function
Slave
⇒ Master
(Response signature)
AK
error
0 No instruction 0 No response
1 Read parameter value 1
2
11
Transmit parameter value
(word)
Transmit parameter value
(double word)
Transmit parameter value
(byte) 7 1)
2 Write parameter value
(data type: word) 1 Transmit parameter value
(word) 7 1)
3 Write parameter value
(data type: double word) 2 Transmit parameter value
(double word) 7 1)
10 Write parameter value
(data type: byte)
11 Transmit parameter value
(byte) 7 1)
1) Instruction cannot be executed (error code)
Output data
2.2.1 Parameter Channel
2.2.1.1 PKE Parameter
Signature Value
Instruction signature