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out 10 groups of data at most. When data staved exceeds 10 groups, external computer
could send out OFH orders many times and continually refer to the 10 groups of data until
all data is obtained.
8.2Test process controlled by host computer (serial
communication of idle double idle and general)
After preheat, the instrument is in the state of test (cursor is on
Test
)
8.2.0 External computer gives out orders, and selects Strokes, IGN.M. mode and fuel
kind.
8.2.1 External computer gives out: 09H (indicating start zeroing)
Correspondence of instrument: 00H (indicating that the instrument has opened air pump,
zeroing valve and is carrying on 30-second zeroing)
Once 30-second zeroing completes, if qualified 06H (ACK) will be given by the
instrument and if unqualified 15H (NACK) will be given. Air pump and zeroing valve within
the instrument shall be shut off.
If the external computer gives out 09H again and again during the process, the instrument
sends back 00H indicating that zeroing is on the way and will only stop when instrument
corresponds ACK (06H) or NACK (15H).
8.2.2 External computer sends: 08H (indicating starting HC remained check )
Correspondence of instrument: 00H (indicating air pump is switched on and the
30-second HC remained check is running)
30-second HC remained check ends, and instrument sends back 06H (ACK) once
qualified, however, it sends back 15H (NACK) once unqualified.
The external computer could send 08H again and again during the process. If HC leftover
test is not completed, the instrument sends back 00H until the ACK (06H) or NACK (15H)
is corresponded.
8.2.3 External computer sends: 03H (indicating to take real-time data)
The instrument corresponds ACK(06H), HC, CO, CO
2
, O
2
, NO
x
, n, T, λ and check sum.
8.2.4 External computer sends: 09H (indicating the end of test, the take-out of probe and
start-up of zeroing)