Frequently Asked Questions
Mon-Fri, 9am to 5pm
U.S. Mountain Time:
Chat With Us
January 27, 2009
What is battery life, assuming you don’t have the LED on all the time?
Brightness? About the same as WS2812?
These have a WS2812-equivalent inside so presumably you control them with exactly the same protocol as any WS2812 device, like this one: https://www.sparkfun.com/products/11821 and its accociated breakout board https://www.sparkfun.com/products/11820 (except that the led voltage and mcu voltage are tied together as in the 4-pin WS-2812B.)
Tutorial - Hackers in Residence - Hacking MindWave Mobile
about a year ago
Uou’re probbaly not going to get anything too useful from the raw data, since it’s the frequency that matters. Thus only really reliable values are the computed Attention and Alertness: it’s probably MindWave’s secret sauce in the ASIC that’s computing it from whatever random wave it can pick up from your frontal cortex, then analyzing the frequency spectrum of it. There used to be devices like this you could by to do meditation feedback.
But IIRC from a few years ago these things were also introduced to pick up eye blinks - is it useful for detecting eye blinks? You could use it to send commands by blinking your eyes….
about a year ago
Looks like it was just a matter of signal strength - where my laptop was reporting about -70 dB signal strength, the dongle was reporting over -90. It has a little dinky antenna, so reduced range is expected.
Still working on getting it working with “Raspbian GNU/Linux 7”. It might be a power thing, my power supply is rated at 700 ma and the Wifi might need more power. It associates OK, gets an IP address OK, then immediately disconnects. This process repeats itself over and over. Also FWIW wpa_supplicant requires you to broadcast your SSID (there may be a workaround):
Sep 25 23:03:30 pi-w wpa_action: creating sendsigs omission pidfile: /run/sendsigs.omit.d/wpasupplicant.wpa_supplicant.wlan0.pid
Sep 25 23:03:30 pi-w wpa_action: bssid=00:21:29:a9:39:b7
Sep 25 23:03:30 pi-w wpa_action: ssid=NSAMONITORINGSTATION
Sep 25 23:03:30 pi-w wpa_action: id=0
Sep 25 23:03:30 pi-w wpa_action: mode=station
Sep 25 23:03:30 pi-w wpa_action: pairwise_cipher=TKIP
Sep 25 23:03:30 pi-w wpa_action: group_cipher=TKIP
Sep 25 23:03:30 pi-w wpa_action: key_mgmt=WPA2-PSK
Sep 25 23:03:30 pi-w wpa_action: wpa_state=COMPLETED
Sep 25 23:03:30 pi-w wpa_action: ip_address=192.168.1.106
Sep 25 23:03:30 pi-w wpa_action: address=00:c3:16:a0:c3:ce
Sep 25 23:03:30 pi-w wpa_action: WPA_IFACE=wlan0 WPA_ACTION=DISCONNECTED [/code]
Not really, you need a USB driver and an Ethernet (and probably IP and TCP/USB) protocol stack, which would not be likely to fit in an Arduino (maybe a Mega).
The Arduino Wifi shields are expensive because the TCPIP stack is offloaded to the shield (it probbaly lives on the Wifi module itself, like the Wifly GSX module), so all the Arduino has to do is exchange serial data with the shield. The shield then takes care of the rest.
Yes - does it work with Raspberry Pi? What is current requirement?
about 2 years ago
Another alternative is to dumpster dive for telco cross-connect wire. Telco techs toss that stuff by the mile. It’s 24AWG solid, but it solders well to all but the smallest or most tightly packed SMDs. I have hundreds of feet of the stuff. You can buy it for about $50 per thousand feet (for two conductors.)
Depend on how much heat or voltage drop you can tolerate: http://www.cirris.com/testing/resistance/wire.html
Forgot your password?
No account? Register one!