Transcript Slide 1
Audible Memo Board (07306)
The Project
Recording an appointment
The Team
Customer: Irene
Sponsor: Tala Hopkins
Consultant: Dr. Hopkins
Advisor: Dr. Slack
Recording an appointment on the calendar
Press calendar
button
Our Customer Irene needed a calendar that she
could use in spite of being blind and having a poor
sense of touch in her fingertips. Our solution is a
calendar that lets her easily record and playback
voice messages.
Announce date
and recorded
messages
Press record
button
Announce that
recording on
that date will
start after tone
Goal
Left to right: Luis Piedrahita (ISE), Joel Forman (ME), Zebo Qiu (EE),
Team Leader Andrew McLean (CE), Andrew Crecca (EE).
To create an audible memo board that
enables a blind person with some
degree of neuropathy in their fingertips
to keep track of appointments. This
device should serve the same purpose
a paper calendar would for a sighted
person able to use a pen.
Features
USER INTERFACE
Speaker
Volume
Record
Power
Playback
Month
Cycle
Erase
Message
Cycle
Memo
Page
Audio
Clock
The audible memo board allows the
user to record and playback multiple
appointments on one day. To help the
user navigate the keyboard, the device
includes
audio
prompts
and
confirmation
for
button
presses.
Appointments can easily be retrieved by
pressing a calendar button which will
automatically play all the messages that
have been recorded on that day. There
is also a playback button that will play
all of the up coming messages
automatically for the user – no need to
find them on the calendar. In addition to
the calendar, the board offers a memo
page. This page is intended for
recording things like phone numbers
and it is accessed by pressing the
memo page button. To announce the
current day and time a clock button has
been included.
YES
Hold record
button down
NO
Play
announcement
until the tone
Stop playing
announcement
Record
appointment
Return to
calendar mode
on selected day
Release record
button
Playback
recorded
message and
date
Return to
calendar mode
on selected day
Electronics Circuit Board
Calendar
Electronics
This record and playback device centers on a microcontroller with multiple interfacing subsystems. Electronics design included a noise-cancelling
microphone, preamplifier, audio codec with microprocessor interface, power amplifier, and finally a speaker. The microprocessor constantly poled userinterface buttons for user control, while also interfacing with the audio stream by storing recordings in a NAND flash memory bank and playing back
through the audio codec. Power supply design featured a wall-mounted supply feeding 12V to voltage conversion circuitry to provide 4 DC voltage levels
needed by the electronics.
Electronics Schematics
Circuitry
Audio Codec
AD74111
Audio In
Microphone
Signal
Conditioning
ADC+Gain
+Filter
Filter to
DAC
Audio Out
Power Amp
Speaker
Serial Data Port
12V
5V
Power Supply Circuitry
3.3V
2.5V
MicroProcessor
User Interface
Buttons
Internal
Program
Memory
Flash
Memory
Interface
Flash Memory