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Hardware| Hardware Overview - RetroCade MegaWing - Papilio Pro

MegaWing MIDI
MegaWing Sound
MegaWing Character LCD
MegaWing Joystick
MegaWing MicroSD
MegaWing Analog Input
Open Source License

RetroCade MegaWing

The Open Source RetroCade MegaWing provides all of the audio hardware needed to make sweet retro music in one convenient and easy to connect circuit board. It snaps into the Papilio Pro and gives it the necessary hardware resources to communicate with the outside world. Continue reading for more information about each hardware section of the RetroCade MegaWing.

MegaWing MIDI

The Midi section of the RetroCade MegaWing implements three MIDI jacks; MIDI IN, MIDI OUT, and MIDI THROUGH. MIDI In is used to connect MIDI instruments such as a MIDI Keyboard, MIDI control board, or MIDI sequencer to the RetroCade synth to send MIDI notes and Control Changes that tell the RetroCade what audio to output. MIDI Through is connected to the MIDI In port and passes everything that comes in over the MIDI In port back out so MIDI devices can be daisy chained together. MIDI Out can be used by the RetroCade to output MIDI data such as timing, change control's or notes.

NameFunctionDirectionArduino PinPapilio Wing PinPapilio Pro PinPapilio One Pin
MIDI TXMIDI Out ConnectorOutput32C0P114P91
MIDI RXMIDI In ConnectorInput33C1P115P92

Technical Details The RetroCade MIDI implementation is closely patterned after the recommended MIDI circuit implementation provided by the MIDI Manufacturers Association. The only deviation from the recommended design is the use of a 3.3V power connection instead of 5V on the MIDI Out connector. This is necessary since the Papilio Pro uses 3.3V voltage levels instead of 5V levels.

MegaWing Sound

Since sound is the most important aspect of the RetroCade Synth we have gone all out with the audio section. Two top of the line 1/4" Neutrik audio jacks (datasheet) are used to ensure solid high quality audio connections. A low pass filter combined with a high speed Delta-Sigma DAC, as outlined in Xilinx App Note 154, allows high quality audio output to be realized. The high speed of the FPGA clock allows the FPGA to do the heavy lifting of the Digital to Analog conversion.

NameFunctionDirectionArduino PinPapilio Wing PinPapilio Pro PinPapilio One Pin
A1-LeftAudio Jack 1 Left ChannelOutput17B1P97P83
A1-RightAudio Jack 1 Right ChannelInput16B0P99P85
A2-LeftAudio Jack 2 Left ChannelOutput18B2P92P78
A2-RightAudio Jack 2 Right ChannelInput19B3P87P71

MegaWing Character LCD

A 16x2 HD44780 compatible Character LCD is used to provide standalone control and feedback for the RetroCade. A standard backlight is provided for easy visibility in low light situations.

NameFunctionDirectionArduino PinPapilio Wing PinPapilio Pro PinPapilio One Pin
LCD_ContrastContrast adjustmentOutput46C14P133P16
LCD_RSRegister Select (RS). RS=0: Command, RS=1: DataOutput26B10P62P41
LCD_RWRead/Write (R/W). R/W=0: Write, R/W=1: ReadOutput25B9P95P54
LCD_EClock (Enable). Falling edge triggeredOutput24B8P74P58
LCD_DB4Bit 4Output23B7P78P61
LCD_DB5Bit 5Output22B6P80P63
LCD_DB6Bit 6Output21B5P82P66
LCD_DB7Bit 7Output20B4P84P68

MegaWing Joystick

A really slick TPA511GLFS digital joystick is included to make navigating menu's a snap. It provides four directions and select in a compact fingertip controlled form factor.

NameFunctionDirectionArduino PinPapilio Wing PinPapilio Pro PinPapilio One Pin
Joy_LeftJoystick LeftInput28B12P57P34
Joy_DownJoystick DownInput29B13P55P32
Joy_SelectJoystick SelectInput31B15P47P22
Joy_RightJoystick RightInput27B11P59P36
Joy_UpJoystick UpInput30B14P50P25

MegaWing MicroSD

The MicroSD (Secure Digital) socket expands the RetroCade with GigaBytes worth of storage space for your audio and configuration files. SD Fat libraries over the standard SPI interface allows files to be copied directly from your computer's filesystem onto an uSD card that can be read by the RetroCade.

NameFunctionDirectionArduino PinPapilio Wing PinPapilio Pro PinPapilio One Pin
SD_DOData Out [MISO]Input42C10P126P10
SD_DIData In [MOSI]Output44C12P131P12
SD_SCKClock [SCLK]Output43C11P127P11
SD_nCSCard Select (Active Low)Output45C13P132P15

MegaWing Analog Input

16 Analog inputs allow the RetroCade to be turned into a custom controller to implement your wildest controllerism ideas. The Analog header allows you to connect up to sixteen analog devices such as sliders, knobs, and analog joysticks. The header is even compatible with the Seeed Studio analog Grove devices when used with a Grove to Brick adapter. Easily add Grove Sliders, Grove Joysticks, or any other Analog Grove device.

The 16 analog channels are implemented with two ADC088S102CIMTX 8-bit, 8 Channel, SPI ADC's that are capable of sampling at speeds up to 1Msps.

NameFunctionDirectionArduino PinPapilio Wing PinPapilio Pro PinPapilio One Pin
ADC1_SCLKClock [SCLK]Output34C2P116P94
ADC1_DINData In [MOSI]Output36C4P118P98
ADC1_DOUTData Out [MISO]Input35C3P117P95
ADC1_nCSCard Select (Active Low)Input37C5P119P2
ADC2_SCLKClock [SCLK]Output38C6P120P3
ADC2_DINData In [MOSI]Output40C8P123P5
ADC2_DOUTData Out [MISO]Input39C7P121P4
ADC2_nCSCard Select (Active Low)Input41C9P124P9


RetroCade MegaWing is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.
RetroCade MegaWing copyright Jack Gassett, Gadget Factory.


RetroCade MegaWing Design Files
Community Links


RetroCade MegaWing

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RetroCade MegaWing Schematic

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Assembly View

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Page last modified on December 06, 2012, at 01:29 PM