phaddar poster rev 2

canolaokahumpkaElectronics - Devices

Nov 2, 2013 (3 years and 9 months ago)

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(
P
ortable
HA
rd
D
isk
D
igital
A
udio
R
ecorder)

phaddar (
fad
är’
) noun. 1. A small electronic component
that interfaces a dynamic microphone with a standard IDE
hard disk. This system has the ability to record at least an
hour of CD quality audio data (16 bits of resolution and a
44.1 kHz sampling rate). The data that is stored on the hard
disk can be downloaded to a PC over the serial port at a
later time. Advantages to the system include scalability,
portability and low cost. 2. Indian word for “worthless”

Put that here


IDE Hard Disk


Microcontroller
-

Microchip PIC 16HC64


Analog to Digital Converter
-

Cirrus CS5331


XLR Connectors


Serial Connector

Order of events for microcontroller chip in recording mode



Spin up drive


Wait for drive ready


Write LBA address to hard disk


Output recording status to LED


Send command for start sector recording


Wait for LRCK signal from A/D to go low


Send data to sector


Update end data address


Check for stop recording command from user button


Check for disk full


Loop to “Send command for start sector recording”



Order of events for microcontroller in downloading mode




Setup for serial communication to computer


Wait for signal from PC to begin downloading


Send size of data string to PC


(three byte LBA address of last recorded sector)


Wait for confirmation or error signal from PC


Send data stream to PC until last used sector is


transmitted


Obtain high quality audio samples for engineering
analysis at a reasonable cost.


Interference between consecutive recordings over the
same physical portion of tape.



Loss of audio fidelity with time, as the tape wears out.



Tape Media limits true frequency response.


Costly



Often Requires Proprietary Interface Card



Very Limited Storage Capacity