ECE 477: Digital Systems Senior Design
Last Modified: 07-29-2017
User Manual
Year: 2017 Semester: Spring
Creation Date: April 13,2017
Author: Wuxiucheng Wang
Team: 15
Project: GUITAMATIC
Last Modified: July 29, 2017
Email: [email protected]
1.0 Product Description
Hiring a guitarist to play at your venue can be a daunting and expensive process.
GUITAMATIC is an automatic guitar player that can fit easily on a wall or a table at your
venue and play music all day long. Unlike a guitarist, GUITAMATIC does not get tired and
can play any song you can think of. Just download the midi file and click play on the app and
entertain your customers. This is not the only benefit you can get from GUITAMATIC, you
can also use it to “learn by example”. Watch GUITAMATIC play your favorite songs at any
speed so that you can practice or jam along with it.
The product includes:
- One electric guitar
- One electric guitar amplifier
- One GUITAMATIC support structure
 Ten L-shape metal supports
 Four small L-shape bars
 Two metal support sheets
 Fifty screws, washers and nuts
- One GUITAMATIC mechanical package
 Thirty 24V solenoids
 One Strumming mechanism
- One GUITAMATIC electronic package
 One microcontroller
 One Bluetooth module
 Five solenoid drivers
 Connection cables
 One 24V power supple
 Two power cable
 One micro USB-B cable
- One User Manual
- One Safety Instructions package
2.0 Product Illustrations
2.1 Complete System:
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ECE 477: Digital Systems Senior Design
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String Nuts
Wood Panel
Solenoids for string-pressing
Left-Hand
Mechanism
Support
Power Cable and
signal cables
Right-Hand
Mechanism
Support
Strings
Solenoids for string-plunking
Microcontroller and
Bluetooth Circuitry
Guitar
Amplifier
110V
Wallplug
Guitar
Control
Strumming
Mechanism
24V Power
Supply
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ECE 477: Digital Systems Senior Design
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2.2 Features:
Solenoids for string-pressing
Left-Hand
Mechanism
Support
Solenoids for string-plunking
Power Cable and
signal cables
Guitar
Control
Solenoids for string-pressing
on second fret
Solenoids for string-pressing
on first fret
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ECE 477: Digital Systems Senior Design
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Solenoid Driver Board
3.0 Setup Instructions
Power Setup:
1. Connect 24V power supply to wall-plug. The 24V power supply will power up the
solenoids and the strumming mechanism. Once the 24V power supply is connected, the
GREEN indicators on the solenoids driver will light up.
2. Connect the 5V USB adapter to the wall-plug, and then connect to the microcontroller,
once the USB is connected, the GREEN indicator on the microcontroller will light up.
3. Connect a power cable to the electric guitar amplifier (optional), once connected, switch
on the amplifier from the back.
Bluetooth Connection:
1. Once the microcontroller is powered up, an RED LED indicator on the Bluetooth module
will flash (ready to pair).
2. Use a smart phone and download the control app from the official website
(https://engineering.purdue.edu/477grp15/) or from Google Play Store.
3. Open the APP
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ECE 477: Digital Systems Senior Design
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4. Click the “Bluetooth” button to connect to GUITAMATIC
5. Select the GUITAMATIC Bluetooth connection, usually the name appears as ‘HC-06’
6. Once connect to GUITAMATIC, MIDI file uploading and control functions, such as
‘play’ and ‘pause’ will be ready.
7. Upload your MIDI file and then enjoy the music created by GUITAMATIC.
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ECE 477: Digital Systems Senior Design
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4.0 Usage Instructions
4.1 – Updating firmware:
4.1.1 Download the newest version of a program called DFuse from ST’s
website (st.com) and open it.
4.1.2 Download the newest version of firmware from our official website
(https://engineering.purdue.edu/477grp15/).
4.1.3 Connect a jumper between pins Boot0 and VDD and Boot1 and GND (use
the diagram above).
4.1.4 Connect a USB cable from your computer to the microcontroller board
and press reset on the microcontroller board until you can see it on DFuse.
4.1.5 Load the new firmware file on DFuse and press upload.
4.1.6 Take off the jumpers and reset the microcontroller.
4.2 – General usage:
4.2.1 Follow power setup and Bluetooth connection procedure mentioned in
section 3.
4.2.2 Download a midi file from the internet onto your android phone.
4.2.3 Open our app and load the midi file and press transfer.
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ECE 477: Digital Systems Senior Design
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4.2.4
4.2.5
After the transfer is complete, press play and enjoy.
To stop, press the stop button and after you are completely done, unplug
the power supply.
4.3 – Change/adjust solenoid:
4.3.1 Raise the base that the solenoids are on by loosening the nuts.
4.3.2 Hold the solenoid with one hand, and unscrew its nut from the button with
the other hand.
4.3.3 Once it’s loose, you can move it around and retighten the screw, or
remove the nut and the solenoid.
.
5.0 Troubleshooting Instructions
Common issues
Probable causes
The guitar is playing the
(1) The guitar is not tuned
correct music but the sound
well.
is off tune.
The string is making noise
when GUITAMATIC is
playing music.
(1) The height of the support
structure is not properly
set.
(2) Some objects appear on
the guitar strings.
The solenoid does not go
back its original position
after playing.
(1) The solenoid tip gets
stuck by a string.
(2) There are some objects
that stick on the solenoid
plunger.
(3) The solenoid return
spring is broken
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Solution Steps
Use a guitar tuner (can be an
electronic tuner, an App or a
webpage application) to tune
each string until all the
strings are adjusted.
(1) Use a screw driver to
loosen the screws on both
sides of the L-shape
metal supports, then
readjust the height of the
metal support sheets until
a desired height is
reached.
(2) Clean the guitar fret
boards using an air
blower or a clean towel
until no object is
blocking the strings.
(1) Use your hand to pull the
solenoid tip out of the
string. You may need to
readjust the position of
the solenoid. Simply
unscrew the nut under the
metal sheet panel, move
the solenoid to its desired
position and then rescrew the nut back.
(2) Remove the object that is
stuck on the solenoid
plunger or use a clean
towel to clean the
plunger.
(3) You can bend the return
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ECE 477: Digital Systems Senior Design
Microcontroller is not
working.
(1) Power supply voltage is
not correct.
(2) Power supply voltage is
not connected to the
correct port.
(3) Supply a high voltage
through the wrong port.
(4) Microcontroller chip is
broken.
(5) Microcontroller internal
program is erased by
accident.
(6) Voltage regulator is
broken by an unexpected
high voltage.
Last Modified: 07-29-2017
(1)
(2)
(3)
(4)
(5)
(6)
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spring to a proper shape
or replace the spring.
Please contact us if you
want to replace the
spring.
Please make sure to
supply 5V from a USB
adapter or from a PC
USB to USB port to
external power port.
Make sure the supply
voltage is higher than
4.5V and the voltage
should be stable. Please
do not directly connect
3.3V to the VDD pins
You may accidentally
connect a high voltage
(higher than 5.5V)
through a VDD pin, this
high voltage may be
permanently damage the
microcontroller.
If the internal program is
erased by accident. You
may either send the
microcontroller back to
us or download the
program from our official
website and reprogram
the microcontroller using
USB or SWD.
Voltage regulator will be
permanently damaged by
a voltage that is higher
than 14V.
If the microcontroller or
the voltage regulator is
damaged, please send it
back to us.
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