Gas Type
Holds the decimal place holder and the
gas type code. The most significant byte
(MSB) holds the number of decimal places
to be used in calculations for this gas.
This decimal locator applies to all
subsequent values of gas readings within
other registers. This can be read by the
instrument. The least significant byte
(LSB) holds a code which identifies the
gas type. This can be read by the host.
MSB = Decimal place holder $01 to $FF
LSB = Gas type code $01 to $FF
$01 CO Carbon Monoxide
$02 H
2
S Hydrogen Sulfide
$03 SO
2
Sulfur Dioxide
$04 NO
2
Nitrogen Dioxide
$05 Cl
2
Chlorine
$06 ClO
2
Chlorine Dioxide
$07 HCN Hydrogen Cyanide
$08 PH
3
Phosphine
$09 H
2
Hydrogen
$0B CO
2
Carbon Dioxide
$0C NO Nitric Oxide
$0D NH
3
Ammonia
$0E HCl Hydrogen Chloride
$14 O
2
Oxygen
$15 CH
4
Methane
$16 LEL Lower Explosive Limit
(Combustible Gases)
$17 C
6
H
14
Hexane
$1A C
5
H
12
Pentane
$1B C
3
H
8
Propane
$4D C
2
H
6
O Ethanol
$50 C
2
H
4
Ethylene
$6F C
3
H
6
Propylene
$C9 C
4
H
10
Butane
Examples: