| Start-up
36 | CO2 Incubator Basic VWR
Chapter 5
Device response for temperature and CO
2
Data:
Nominal value x 10, (2 bytes, integer)
Nominal value, (4 bytes, floating point number)
Internal use, (5 bytes for CO
2
, otherwise 7 Bytes)
Command list - Requesting failure codes
Command:
1001 0000 (90
H
)
Data:
none
Response - Reading failure codes
The microprocessor returns a total of 10 bytes (5 integer values). Each integer value represents a
current failure code in the assigned control loop (incubation temperature, CO
2
content, general).
The failure code General failure belongs to a superior failure that is shown simultaneously in all
displays (e.g. failure code 99).
The failure codes for incubation temperature and decontamination temperature are shown in the
temperature display, the codes for CO
2
are shown in the CO
2
display. Value "---" shows that there
is no current failure.
Faulty response from control unit:
If a returned response is incomplete or faulty, the CPU responds with an NAK (15
H
, only 1 byte,
without frame). Otherwise, the command code (with pertaining length information) is regarded as a
response and the data that may be required is transmitted.
Particularities during data communication:
For the data communication between PC and microcontroller, the following particularities must be
observed:
The microprocessor stores an int or unsigned int value with the sequence <Highbyte>,
<Lowbyte> in the memory. For the PC, this sequence is reversed. The microcontroller transmits
these values in its format, i.e. the PC must reverse the sequence of the bytes. For floats, there is
no difference.
Example: Temperature data request and response
To Next Page
Loading...
