sample lossage with the wifi shield at 1000 Hz
Dreambuild
China
Was using the wifi shield to transfer data to my laptop, but there is constant samples lost. Each sample lost will cause some spike in the LLT and the green light on the wifi shield will blinks as the sample lost happened. Any suggestions to solve this?
Comments
Are you using equipment manufactured by OpenBCI? Or are you using boards you have designed and created yourself (such as you mention your own Cyton design on the forum?)
The original Wifi Shield always worked well with the Ganglion board. But when used with Cyton, in certain circumstances, would not perform as expected. This was researched and determined to be an issue with the Vdd power filtering on the Shield. A revised Shield is in the works. See this thread:
https://openbci.com/forum/index.php?p=/discussion/2108/measured-shield-regulated-3-3v-supply-has-6v-dip-at-1-second-intervals-with-resonant-ringing
The standard suggestion with old Shield and Cyton, was to use a separate 6V AA pack to power each board (Cyton and Shield), and to use the 'Direct' UDP x3 mode. The TCP mode draws too much current and causes power spikes. These suggestions may give a workaround until the repaired Shield is available.
If you are only doing EEG, then 1000 Hz is usually overkill. Try dropping to 500 Hz or 250 Hz.
William