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Product GPS-11115 | about 3 months ago

FYI- the dsPIC33 on this has a maximum internal oscillator speed of 80 MHz, which is misleading anyway (clock rate != CPU speed), since it is divided by 2 to get the actual processor instruction clock, this part is really 40 MIPS.

The dsPIC30 used a 120MHz maximum clock, divided by 4 to get a 30 MIPS CPU.

Product SEN-09694 | about 5 months ago

I’m running into some issues with my code and I hope someone could help. If I hard code the readings and calibration data that is shown on P.13 of the datasheet, I get the results shown in the datasheet, however, when I pull the real data and the real calibration off of the device, the pressure is way low (about 3.55psi, 24,500 Pa). The temperature readings are accurate, and when I change the oversampling, the results I get for pressure are consistent (about the same + expected noise) for oversampling of 0, 1, 2 and 3. I did have to play around with typecasting a bit to get things to match up with the reference code. I’d like to experiment with some other calibration data and readings to validate my calculations- at the moment, I have:

AC1=8515
AC2=-1156
AC3=-14476
AC4=34169
AC6=24839
B1=5498
B2=61
MB=-32768
MC=-11075
MD=2432

Oversampling (for this example) is 2

UT reads as 35405, which calculates to 21.5C

UP reads as 171740 (after the shift for oversampling), which results in a pressure of 24957, or 3.619psi. (way too low for my altitude, about 800ft ASL)

I’d appreciate if someone could either run my calibration an readings into their code and see if they get the same, or send me your calibration and readings I could run through my code.

FYI: this is being done in C on a PIC32 on a Digilent Uno32. I do plan to share the code once it works. I’ve got a bunch of things running on the same I2C bus under a scheduler I wrote- each sensor can have a different interval and it can do other operations on a different device while the I2C while the pressure sensor is waiting the requisite time.

News - Building a Cheap Thermoca… | about 9 months ago

No, it’s not. I just looked over the license, as far as I can tell, the only usage restrictions are related to dangerous applications: “DANGEROUS APPLICATIONS. Licensee warrants that Licensee will not use Software in a dangerous […] without the express prior written consent […]”

News - Building a Cheap Thermoca… | about 9 months ago

Essentially this project is in my neverending queue of in-progress projects- instead of using the very expensive Melexis module, I was planning on using a solar “cigarette lighter” – a small parabolic reflector, with a (lots cheaper version, SEN-09570) Melexis sensor at the focus.
I’m not an Arduino fan- I was planning on using a PIC32, but the developer’s GUI definitely looks like something I can leverage.