BART LABDMM2, Руководство пользователя

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LABDMM 2 USER GUIDE
MO.LABDMM2.560.ENG.R1
Pag. 26
CC : 2 byte integer value (binary format): length in points of the 3° sub-cycle: 0 = no data
DD : 2 byte integer value (binary format): length in points of the 4° sub-cycle: 0 = no data
EE :
2 byte integer value (binary format): length in points of the 5° sub-cycle: 0 = no data
Read Log Index Data and Time COMMAND
LABDMM2 has got an internal clock calendar.
You can retrieve the starting data and time of each sub-cycle using the following command
command L70000X<cr>
Where X= 1 character : ‘0’ .. ‘4’ : sub cycle index
answer L7NssmmhhDDMMYY<cr>
the answer is a binary format
N : 1 byte : 0..4 : sub cycle index
00 : 2 byte : second : always 0
mm : minutes
hh : hour
DD : day : 1..31
MM : month : 1..12
YY : year : the Year field is just 2 bytes. It represents the years elapsed from 2000
so the value 19 means 2019 (example : 19
→
2019)
START DOWNLOAD COMMAND
This command must be sent just once.
command L600000<cr>
answer LABDMM2 answer with a data packet as descripted below.
Data packet format
Since it may be necessary to download a large number of data, instrument responds with a
message with a binary format consisting of:
Cycle with temperature : NNNNPPPPTTTTT (12 byte)
Cycle without temperature : NNNNPPPP (8 byte)
The first 4 bytes (binary format) represents
NNNN is the sequential index points (integer
value) ; Starting from 0 and ending to the number of points inside the datalog. It increments by
1 each time a new data packet is required.
PPPP
(4 bytes binary format) represents the pressure in floating point according to IEEE754
TTTT
(4 bytes binary format) represents the temperature in floating point according to IEEE754
The application program must check that the index sequence is correct .
NNNN value must increase one by one.
On the basis of the sequential index the application program can calculate the time stamp of
the pressure value by multiplying the sequential index by the time interval between two
acquisition points.
NOTE To ask the next data packet just send the character ‘@’
To repeat the transmission of a data packet just send the character ‘$’
To abort a download just send the character ‘;’
Note
Caution: It is not possible to download data while a datalog cycle is in progress