Figure 6.15 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 user 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.
User 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 can be controlled by SW0. The audio codec used on the DE2-70 board has two channels, which can be turned ON/OFF using SW1 and SW2.
Figure 6.17 illustrates the setup for this demonstration.
Figure 6.17. Block diagram of the Music Synthesizer design
Demonstration Setup, File Locations, and Instructions
•Project directory: DE2_70_Synthesizer
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