APPENDIX A-4: M Signal I/O Definitions
T200H/M and 200EH/EM Menu Trees (05147J DCN7141)
A-16
Signal Name
Bit or Channel
Number
Description
B status outputs, U27, J1018, pins 1
–
8 = bits 0
–
7, default I/O address 324 hex
ST_CO2_CAL
15
0
0 = in CO
2
calibration mode
1 = in measure or other calibration mode
1–7
Spare
Front panel I
2
C keyboard, default I
2
C address 4E hex
MAINT_MODE
5 (input)
0 = maintenance mode
1 = normal mode
LANG2_SELECT
6 (input)
0 = select second language
1 = select first language (English)
SAMPLE_LED
8 (output)
0 = sample LED on
1 = off
CAL_LED
9 (output)
0 = cal. LED on
1 = off
FAULT_LED
10 (output)
0 = fault LED on
1 = off
AUDIBLE_BEEPER
14 (output)
0 = beeper on (for diagnostic testing only)
1 = off
Relay board digital output (PCF8575), default I
2
C address 44 hex
RELAY_WATCHDOG
0
Alternate between 0 and 1 at least every 5 seconds to keep
relay board active
RCELL_HEATER
1
0 = reaction cell heater on
1 = off
CONV_HEATER
2
0 = converter heater on
1 = off
MANIFOLD_HEATER
10
3
0 = bypass or dilution manifold heater on
1 = off
IZS_HEATER
4
0 = IZS heater on
1 = off
CO2_CELL_HEATER
15
0 = CO
2
sensor cell heater on
1 = off
O2_CELL_HEATER
11
5
0 = O
2
sensor cell heater on
1 = off
SPAN_VALVE
6
0 = let span gas in
1 = let zero gas in
ZERO_VALVE
3
0 = let zero gas in
1 = let sample gas in
CAL_VALVE
7
0 = let cal. gas in
1 = let sample gas in
AUTO_ZERO_VALVE
8
0 = let zero air in
1 = let sample gas in
NOX_VALVE
9
0 = let NO
X
gas into reaction cell
1 = let NO gas into reaction cell
NO2_CONVERTER
4
0 = turn on NO
2
converter (measure NO
x
)
1 = turn off NO
2
converter (measure NO)
07270D DCN7141