Search found 15 matches

by vikebo
Mon Mar 23, 2015 10:01 pm
Forum: General Discussion and Questions
Topic: Logging ADC data to SD-card
Replies: 9
Views: 7879

Re: Logging ADC data to SD-card

Manitou, didn't see your plot before today, it illustrates it very well. Probably a good idea to store data in a buffer first. I want to find the different options for sampling and storing data at a few kilosamples for some minutes, so data will have to be written while still measuring. Also looking...
by vikebo
Sun Mar 22, 2015 10:06 pm
Forum: General Discussion and Questions
Topic: How to get the Bluetooth module working (JYMCU...)?
Replies: 15
Views: 9233

Re: How to get the Bluetooth module working (JYMCU...)?

Hello, I've also got one of the Bluetooth modules now and since I want to use a higher transfer rate than 9600 BPS, I have tested the AT mode. Tried to do everything from the MicroPython board since I may use the module with different boards and want them to do any required modifications on their ow...
by vikebo
Mon Mar 16, 2015 8:51 pm
Forum: General Discussion and Questions
Topic: Logging ADC data to SD-card
Replies: 9
Views: 7879

Re: Logging ADC data to SD-card

Also tried using timer callback to read the ADC today with better results. Inspired by one of Dave Hylands' examples, I made a class for timer 4. I was able to achieve a sample rate slightly above 10 kHz, higher freq-settings for the timer gave just below 100 us between samples. As can be seen below...
by vikebo
Mon Mar 16, 2015 8:27 pm
Forum: General Discussion and Questions
Topic: Logging ADC data to SD-card
Replies: 9
Views: 7879

Re: Logging ADC data to SD-card

Thank you for your replies. As can be seen, there are two types of discontinuities. The short ones of ~1 ms are at ~8 ms intervals, and long ones of 10 - 12 ms with "random" intervals (sometimes several in a short time). I think the worst with these is that the timestamp counter for pyb.micros seems...
by vikebo
Sun Mar 15, 2015 9:08 pm
Forum: General Discussion and Questions
Topic: Logging ADC data to SD-card
Replies: 9
Views: 7879

Logging ADC data to SD-card

Hello, I'm trying to store data read from the ADC to a file on the SD-card. X1 is connected to an external function generator configured to a 10 Hz triangular wave. As this plot shows there are some discontinuities in the data: adc.png I also tried storing the variable of the for-loop to check if th...