14
2.6.3 Commands through USB connection
The sequence that has to be sent in order to read or write the value of a
variable must have the following structure:
1. #SLED (1 byte): number of the SLED whose parameters we want to read or
write. The first SLED contained in the source is assigned number 1 and so on.
2. ADDRESS (1 byte): the address of the variable we want to read or write. The
addresses of the different parameters are given in Table 2.
3. FLOAT 32bits: in case of a writing command, the new value for the variable
we want to modify has to be introduced here with this format. In case of a
reading command, nothing has to be sent.
4. SPACE /n: end of the message, where a space “ “ has to be included. In case
of a reading command, directly introduce the space after the address.
Comments
•
It is not recommended to overwrite the values of the variables that are
shadowed (minimum and maximum allowable T, KP and KI).
•
Reference T is the target temperature for the temperature control. The default
value is 20 ºC and it is not recommended to introduce a lower one.
•
Addresses 0x20 and 0x24 are not used.
•
Modifying the maximum and minimum allowable currents through the TEC will
affect the velocity of the temperature control.
•
Instantaneous T of the SLED is the real temperature of the SLED while
measured T of the SLED is its value after applying a filter. Both values can only
be read, not written.
Sending 0xFFFFFFFFFFFF (6 bytes) followed by /n will restore all the
source parameters to their Factory Mode values
Not following the recommendations on this page can result in
undesired behaviour that can cause damage to the light source,
which is NOT covered by Pyroistech’s warranty
Variable
Address
Reference T (ºC)
0
Minimum allowable T (ºC)
4
Maximum allowable T (ºC)
8
Proportional gain KP
12
Integral gain KI
16
Variable
Address
Maximum I through TEC (A)
28
Minimum I through TEC (A)
32
Reference I through the SLED (mA)
36
Instantaneous T of the SLED
40
Measured T of the SLED
44
Table 2. Variables and their corresponding addresses
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