Activities/Turtle Art/Using Turtle Art Sensors

From Sugar Labs
< Activities‎ | Turtle Art
Revision as of 19:06, 6 November 2010 by Tonyforster (talk | contribs) (Created page with "CAUTION. APPLYING EXTERNAL POWER SOURCES TO THE XO LAPTOP'S MICROPHONE INPUT CAN CAUSE PERMANENT DAMAGE. BE SURE YOU READ AND UNDERSTAND THE FOLLOWING BEFORE CONNECTING POWER SOU...")
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search

CAUTION. APPLYING EXTERNAL POWER SOURCES TO THE XO LAPTOP'S MICROPHONE INPUT CAN CAUSE PERMANENT DAMAGE. BE SURE YOU READ AND UNDERSTAND THE FOLLOWING BEFORE CONNECTING POWER SOURCES TO YOUR LAPTOP.

The OLPC XO can measure external inputs with its microphone jack

Specifications

Standard 3.5mm 2-pin switched mono microphone jack; selectable 2V DC bias; selectable sensor-input mode (DC or AC coupled)

If using a stereo plug it is the red wire plus the earth.

It is protected at the input by a 5V zener diode and has a measurement range of 0.3V to 1.9V. The allowable input is -0.5V to 5V Inputs outside this range will cause excessive current and damage.

Addition of a 150k ohm series resistor would (I expect, no guarantee) give a reduced sensitivity in voltage mode (0-4V) but allow inputs to +- 100V without damage. Input impedance in resistance, volume and pitch modes is much lower but a 1k ohm series resistor should still allow inputs to +-12V.

Retrieved from "https://wiki.sugarlabs.org/index.php?title=Activities/Turtle_Art/Using_Turtle_Art_Sensors&oldid=58914"