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This demonstration shows how to implement a Multi-tone Electronic Keyboard using DE2-115
board with a PS/2 Keyboard and a speaker.
PS/2 Keyboard is used as the piano keyboard for input. The Cyclone IV E FPGA on the DE2-115
board serves as the Music Synthesizer SOC to generate music and tones. The VGA connected to the
DE2-115 board is used to show which key is pressed during the playing of the music.
Figure 6-23 shows the block diagram of the design of the Music Synthesizer. There are four major
blocks in the circuit: DEMO_SOUND, PS2_KEYBOARD, STAFF, and TONE_GENERATOR. The
DEMO_SOUND block stores a demo sound for users to play; PS2_KEYBOARD handles the users‟
input from PS/2 keyboard; The STAFF block draws the corresponding keyboard diagram on VGA
monitor when key(s) are pressed. The TONE_GENERATOR is the core of music synthesizer SOC.
Users can switch the music source either from PS2_KEYBOAD or the DEMO_SOUND block
using SW9. To repeat the demo sound, users can press KEY1.
The TONE_GENERATOR has two tones: (1) String. (2) Brass, which is controlled by SW0. The
audio codec used on the DE2-115 board has two channels, which can be turned ON/OFF using SW1
and SW2.
Figure 6-24 illustrates the setup for this demonstration.
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