Audio hardware: Difference between revisions
Arjunsarwal (talk | contribs) |
Arjunsarwal (talk | contribs) |
||
Line 19: | Line 19: | ||
* Bias voltage output (short circuit) |
* Bias voltage output (short circuit) |
||
* anything else? |
* anything else? |
||
The paper - 'The One Laptop per Child (OLPC) Audio Subystem' by Jaya (Alsa) provides useful information on the audio subsystem. The link is - |
|||
[www.kgw.tu-berlin.de/~lac2007/papers/lac07_kumar.pdf] |
|||
=== Microphone data input === |
=== Microphone data input === |
Revision as of 02:35, 20 June 2007
These are ideas related to both audio input and output. Please review the hardware specification to see what is already included. Some audio-related ideas are also dealt with in the Radio and Broadcast page.
Microphone
A built in Microphone would be usefully if dirt and echo/feedback could be controlled. If you have a microphone and speakers included with these laptops then then if you include a small peice of software they can be used as telephones or walkitalkies -- like an instant message local channel that is as easy to use as a CB radio. If the hardware looked like a radio, the oporator could use it before they learend how to use the computer.
Sound Codec
The [Hardware specification]] page says the Audio Codec is an Analog Devices AD1888, AC97-compatible audio codec.
Microphone Sensor Input
The microphone input can be used to measure voltage or (using the Microphone bias voltage) resistance. This should enable us to use this as a form of sensor input with the audio analog to digital converter converting the sensor signal to a signal that can be displayed on the screen or logged by the computer. More info is required on the use of the codec in this mode.
- max voltage that can be withstood safely by the mic input
- Voltage corresponding to AD converter full scale.
- Bias voltage output (open circuit)
- Bias voltage output (short circuit)
- anything else?
Microphone data input
The microphone input jack can double as a dataport for some class of devices (when supporting a "DC-coupled" input mode), but a more general-purpose USB analog to digital device would be a great peripheral for the laptop. --Walter