midibox_ay_3_8912 [MIDIbox]

- MIDIbox AY 3 8912

The MIDIbox AY 3 8912 is stuffed with a General Instruments AY-3-8912 sound chip. The AY-3-8912 is a 3-voice Programmable Sound Generator (PSG). The AY 3 8912 and its variants became popular chips in many arcade games, and was used on the Intellivision and Vectrex video game consoles and the MSX, Atari ST, Amstrad CPC, Oric 1, Colour Genie, Elektor TV Games Computer and Sinclair ZX Spectrum 128/+2/+3 home computers as well as the Mockingboard sound card for the Apple II family (etc.). The PSG contains 3 independent channels (A, B and C), a single noise generator, and a single envelope generator. Each channel includes a square wave tone generator and is capable of mixing any combination of the output from its respective tone generator with the noise generator and the envelope generator. Output from each of the 3 channels is then mixed together to produce the final audio output. The MIDIbox AY 3 8912 Control Surface based on a C64 Keyboard and a 4×16 LCD.

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Hardware

1x Core (Core V3, PIC 18F452, MIOS 1.9f)

1x LCD Module: 4×16 LCD (8bit) | see ⇒ (http://www.midibox.org/users/jim_henry/building_a_midibox_lcd_cable.pdf)

1x MIDIBox AY 3 8912 board | see ⇒ midibox_ay_3_8912_board

1x C64 Keyboard (C64 Keyboard, 1xDOUT, 1xDIN)) | see ⇒ midiboxkb_-_using_a_c64_keyboard_as_input

Optional: CS LED Connection Diagram (2-4x DOUT)) | see ⇒ midibox_ay_cs_led

1x OP AMP Mixer for Tone A B C (CHIP: LM324N (4xOP AMP) +/-12V) | see ⇒ midibox_ay_3_8912_mixer

PSU +5V (MBHP Core +5V ⇒ AY 3 8912 board), +/-12V ⇒ OP AMP Mixer | see ⇒ (http://www.ucapps.de/mbhp/mbhp_opl3_psu.pdf)

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Software (MIDIBox AY V1)

MIDIbox AY 3 8912 Software Download (for PIC 18F452, asm, MIOS 1.9f):

MIDIBox AY 3 8912 Application V1.00 RC1a ⇒ mbay18f452v1rc1a.zip (22.11.2009)
Changes @ V1 RC1a : Bankstick (Now You can store up to 127 MBAY Patches on a Bankstick)
Changes @ V0.07 : New Fx Option
Changes @ V0.06 : Name, Save and Load a Patch (No Bankstick Needed (PIC int. EEPROM))

Application upload (main.hex) via MIDI ⇒ MIOS Studio

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User Menu Overview

User Menu (4×16 LCD)

[←] Menu Overview
[F1] Patch Menu: load, name and store MIDIBox AY Patches ⇒ PATCH MENU
[F2] Tune Menu: Detune Tone A, B and C (detune is NOT transpose!) - Details: ⇒ TUNE Tone ABC (MENU)
[F3] Mixer (On/Off Tone A, B and C; On/Off - On/Off Noise @ A,B and C; On/Off Fx Option A,B and C)
[F4] Volume Control: Tone A, B and C [0 to 15 dec.] - Details: ⇒ VOLUME Tone ABC (MENU)
[F5] Envelope Control: Envelope Coarse, Env. Fine, Env. Shape, Env. Assignment to Tone A, B and C - Details: ⇒ ENVELOPE (MENU)
[F6] Midi Channel Tone A B C
[F7] Velocity Menu (Switch Velocity to Volume Tone A, B and C or Noise Period)
[F8] Fx Menu Fx Options - Details: ⇒ Fx Option

Note: [F2] = [SHIFT + F1], F4 = [SHIFT + F3], etc. Notice: The [SHIFT] KEY must be pressed first.

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Menu Navigation

Press [F1] to [F8]
Step to the next Menu with [CTRL]
Step to the previous Menu with [SHIFT] + [CTRL]

Item Navigation:

DOWN ⇒ [CRSR DOWN] (or [RETURN]) - Item pos. +1
UP ⇒ [CRSR UP (+ SHIFT)] (or [ARROW UP]) - Item pos. -1

Change Value:

INCREMENT Value +1 ⇒ [CRSR →] or [+] or [>]
DECREMENT Value -1 ⇒ [CRSR ←|(+SHIFT)] or [-] or [<]

Toggle Tone A, B and C (on/off):

To toggle Tone A B C on/off just use key [A], [B] and [C] (Mixer Menu via [F3])
To add “Noise” - same here.
To toggle ENVELOPE Tone A B C on/off use key [A], [B] and [C] (Envelope Menu via [F5])

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The Commodore 64 Keyboard

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Available MIDI Controllers

Available MIDI Controllers for the MIDIBox AY 8912: See MIDIBox AY 3 8912 CC LIST ⇒ MIDIBox_AY_3_8912_CC_LIST

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Project Status

DONE:

C64 KEYBORD INTERCONNECTION
SERIAL INTERCONNECTION [ CORE :: J7 → 74HC595 → 8BIT OUT [AY ADRESS/DATA] ]
HARDWARE INTERCONNECTION of the AY-3-8912 Sound Chip
6 MAIN MENUS ON LCD
Hardware: OP AMP Mixer for Tone A B C
MIDI EVENT HANDLING (Note On / Note Off)
(DE)TUNE MENU is working
KEYBOARD HANDLING: continuous increment/decrement (via [+]/[-] and the LEFT/RIGHT CRSR Key)
Added a MASTER VOLUME POT [See ⇒ midibox_ay_3_8912_mixer]
MIDI CH TONE A B C adjustable
AY 3 8912 Board (PCB), pdf added (thanks nILS!)
VELOCITY MENU - switch Velocity to to volume Tone A, B, C and Noise Period [Press F7]
Menu Navigation with CTRL key
Keyb.: [CTRL] + [SHIFT] = Step one Menu back
CONTROL CHANGE: CC 1-22 | See ⇒ midibox_ay_3_8912_cc_list]
Created a MIDIBox AY 3 8912 - VOLUME MENU page | [See ⇒ midibox_ay_3_8912_volume]
Enabled PITCH BEND @ Tone A, B and C
SAVE INT. PATCH TO PIC EEPROM (AY Sound Patch Menu)
Fx Option
CS LED'S
Bankstick Patches (MIDIBox AY V1.00)