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tina46e1-b (2017-12) BPG402.om
For transmission of the commands to the gauge, a string (frame) of five bytes is
sent (without <CR>). Byte 1 … 3 form the data string.
Byte no Function
Value
Comment
0
Length of data string
3
set value
1 Data
→
admissible input strings
2 Data
→
admissible input strings
3 Data
→
admissible input strings
4 Check
sum
(from bytes No 1 … 3)
0 … 255
(low byte of sum)
4)
4)
High order bytes are ignored in the check sum.
For commands to the gauge, the following strings are defined (values in decimal
notation):
Command Byte
No
0 1 2 3 4
5)
Set the unit mbar in the display
3
16
142
0
158
Set the unit Torr in the display
3
16
142
1
159
Set the unit Pa in the display
3
16
142
2
160
Power-failure-safe storage of current unit
3
32
2
–
34
Switch degas on
(switched off automatically after 3 minutes)
3
16
196
1
213
Switch degas off (before 3 minutes)
3
16
196
0
212
Set Emission Control Mode to AUTO
6)
3 16 138 1 155
Set Emission Control Mode to MAN
6)
3 16 138 0 154
Power-failure-safe storage of the
Emission Control Mode
6)
3
32
1
–
33
Switch emission on
3
64
16
1
81
Switch emission off
3
64
16
0
80
Set Filament Control Mode to AUTO
7)
3 16 211 0 227
Set Filament Control Mode to MAN
7)
3 16 211 1 228
Power-failure-safe storage of the
Filament Control Mode
7)
3
32
13
–
45
Select filament 1
8)
3 16 210 0 226
Select filament 2
8)
3 16 210 1 227
Power-failure-safe storage of selected filament
8)
3 32 12 – 44
Read
filament
status
3 0 212 – 212
Read
software
version
3 0 209 – 209
Reset
3 64 0 0 64
5)
Only low order byte of sum (high order byte is ignored).
6)
Defines the Emission Control Mode (
→
30):
AUTO = emission on/off automatically controlled by the gauge
MAN = emission on/off controlled via interfaces.
7)
Defines the Filament Control Mode (
→
30):
AUTO = Selection of filament automatically controlled by the gauge
MAN = Selection of filament controlled via interfaces.
8)
The "Select filament x" command can be sent any time but is only executed if
the gauge is in the "Emission OFF" state.
4.9.1.2 Input String (Receive)
Format of the input string
Admissible input strings
