Owner's manual

tina40e1-b (2011-04) 35
Bit 1 Bit 0 Definition
0 0 emission off
0 1
emission 25 μA
1 0 emission 5 mA
1 1 degas
Bit 2 Definition
x reserved for future use
x reserved for future use
Bit 3 Definition
0 ⇔ 1
toggle bit, changes with every
string received correctly
Bit 5 Bit 4 Definition
0 0 current pressure unit mbar
0 1 current pressure unit Torr
1 0 current pressure unit Pa
Bit 7 Bit 6 Definition
x x reserved for future use
Bit No. Definition
Message on display
(only BCG450 353-552
and 353-553)
0 diaphragm sensor error "FAIL Cap"
1 reserved for future use —
2 Pirani sensor error "FAIL Pir"
3 reserved for future use —
4 BA sensor error "FAIL Ion"
5 reserved for future use —
6 hardware failure, EEPROM failure "FAIL EL"
7 reserved for future use —
The software version of the gauge can be calculated from the response value of
byte 6 of the transmitted string according to the following rule:
Version No = Value
Byte 6
/ 20
(Example: According to the above formula, Value
Byte 6
of 32 means software ver-
sion 1.6)
The pressure can be calculated from bytes 4 and 5 of the transmitted string. De-
pending on the currently selected pressure unit (→ byte 2, bits 4 and 5), the ap-
propriate rule must be applied.
As result, the pressure value results in the usual decimal format.
p
mbar
= 10
((high byte × 256 + low byte) / 4000 - 12.5)
p
Torr
= 10
((high byte × 256 + low byte) / 4000 - 12.625)
p
Pa
= 10
((high byte × 256 + low byte) / 4000 - 10.5)
Status byte
Error byte
Software version
Calculation of the pressure
value