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it is less work than i though to get mlx90460 sensor usable for thermal cam.

A project log for mlx90640 sensor works w 800 bytes

Everywhere i read people are excited to get mlx90640 working. here are examples using arduino w 800bytes ram, and 1k with calibrated DEG C

jamesdanielvjamesdanielv 10/16/2018 at 21:440 Comments

i've been trying to get the energy and time to convert all the commands to run on Arduino. the evil scientists at Melexis want you to purchase supercomputers to process float thermopile calculations (or at least a high end arm cortex). i think they did this as a joke. well i brought the bag to the doorstep, and lit fire a few weeks ago  (just watched Billy Madison) with my no float test setup here:

https://github.com/jamesdanielv/thermal_cam_mlx90640

in data sheets for mlx90460 it states:

13.2. Using the device in “image mode”

In some applications may not be necessary to calculate the temperature but rather to have just and image (for instance in machine vision systems). In this case it is not necessary to carry out all calculations which would save computation time or allow the one to use weaker CPU.

In order to get thermal image only following computation flow is to be used:

Supply voltage value calculation (common for all pixels) - 11.2.2.2 

this means for now as a start all i would need to convert are the now epprom saved results from factory, and gather the latest voltage to chip readings from sensor for frame1, and frame 2.

the process is this. capture 1st frame, store voltage to sensor, capture second frame, store voltages to sensor, read 32 columns, display results, read 24 rows down. and by the way. the memory can be read over and over again, as long as the sensor is in step mode, and you haven't ask it to sample sensors again. by the way i had to create my own command to do this, as melexis examples did not have a way to do it out of box. if i'm wrong about it let me know. one of the status registers is below. 

eeprom results no longer need to be in ram and can be put into Arduino thru a table cut and paste with program i created here: 

https://github.com/jamesdanielv/thermal_cam_mlx90640/blob/master/getEEpromDump.zip

and the following calculations below:

i'll upload the complete spec sheet into the files section of this project.

this looks scary, but it is really just AND compare and shift rights and a few bits of subtraction and manipulation of resolution 8bits to left for simulation of what would be float. Ok.. it is scary, but i've got my big boy pants on this week! :)

once this is tested, it will be added to setup files i have for the mlx90460 here:

https://github.com/jamesdanielv/thermal_cam_mlx90640

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