Posts Tagged ‘user projects’

“Really Dumb” MIDI Monitor For RetroCade

Monday, February 10th, 2014


Forum member Offroad recently hit us up with an example project, which is  based on the Papilio Pro and the RetroCade Synth. He’s calling it the Really Dumb MIDI Monitor.  This deserves a bit of explanation:

For starters, Offroad explains what he means by the term, “really dumb meaning: All the fun stuff like printf(“%02c”, byte) happens in RTL state machines…”

The project includes a simple MIDI parser for note on-/off messages. It remembers the state of all keys (all channels are combined, “omni mode”). Maybe this could be useful for some MIDI music experiments with minimal fuss: Excluding UARTs and FIFO (reused modules), the actual RTL code that does all the work is only about two screen lengths.

Here are a couple of links to the actual examples that he created, so make sure to click through and check them out for yourself.

  • Papilio Pro MIDI Monitor – (zip file)
  • meepMeep – (zip file) – This one is a MIDI monitor that actually makes an audible impression with an 18-bit saw waveform.  Offroad says it sounds like a Farfisa!  (See image above) Yikes indeed!

Do any of you guys have anything interesting that you’re working on for the RetroCade?  We’d love to hear about it!  Feel free to post to the forums, or comment on this post!  Right on.

(via the forums, and thanks to Offroad)


Cool QR Code Clock On Graphical LCD

Monday, July 15th, 2013

Sometimes its good to see what other people are up to on their projects. It can serve to spark an idea for your own designs, and this one here is just plain cool. This QR code clock is displayed on a graphical LCD screen, and is totally indecipherable just to look at. You have to take a picture of it with a QR code app to tell the time. Each second, the QR code on the clock changes to update the time. This clock is actually kind of hypnotizing to watch – check out the vid!

The QR code clock was built by Markus Gritsch over at Dangerous Prototypes, his idea built on inspiration from an earlier LED matrix-based QR clock. His clock runs on a PIC32 microcontroller which decodes a time signal from a DCF77 receiver, then calculates a QR code and displays it on the ST7735R graphical LCD at 30FPS. Markus added a layer of polish to the project with some cool effects – when the clock is unable to read the radio signal it displays time in greyscale, but when it locks to the DCF77 signal it starts to trip out with a rainbow-colored plasma effect. Nice work for sure! I wonder how long it would take you to learn to tell the time just by looking at the QR code without scanning it…

Quick question: what are you guys up to in your projects? We would love to feature the fruits of your labor here on the homeblog, so whatever you’re creating, make sure you post it to the forums. We’ll do the rest.

(via Dangerous Prototypes)

Firing Up The RetroCade Synth: First Impressions

Wednesday, July 3rd, 2013

We found another great article by Phillip Howard from Raspberry Pi @ Gadgetoid, this time on Getting Started With The Papilio RetroCade Synth. In the image above, you can see the RedroCade MegaWing plugged into its host Papilio Pro. This is the setup that Phillip used for the purposes of his article.

After some initial fussing with Windows 8 drivers and dealing with a reversed polarity situation from MIDI note on/off commands, Philip found himself having a genuinely great time with the synth. Let’s check out some of his findings from the article:

The beauty of the RetroCade is not that is incorporates an FPGA clone of the legendary Commodore 64 SID and Yamaha YN-2169 chip, but that both these hardware implementations, and the Arduino-like Sketch used to drive them are completely open and user-editable.

Playing with the RetroCade was a nice, Friday-friendly introduction to Papilio and once everything was up and running it was really a joy to play. The synthesizer is alarmingly powerful, and exudes nostalgia, but the software has both room for improvement and the opportunity for any user to delve in and make those improvements.

We really appreciate the kind words and your candor, Philip. I know that many people are excited to give the whole synthesizer hacking thing a go, and your article shows that it is really not as difficult as one might imagine it to be.

This is a great segue to a new blog series we will be sharing with you during the coming weeks in this space. We will be sharing a first-timer’s efforts in using the Papilio Pro, the Retrocade Synth, and the LogicStart! Should be interesting!

You can check out Phillip’s full article on his RetroCade experiences here.

(via Raspberry Pi @ Gadgetoid)

Papilio And pcDuino Together As A USB to 3.3V TTL RS232 adapter

Friday, April 5th, 2013

Here’s a great and simple project using a Papilio One and a pcDuino together for the purpose of making a USB to 3.3V TTL RS232 adapter. This is from Mike Field’s site Hamsterworks where he’s got a full project description and the code to go along with it! Mike says,

I’ve got a pcDuino and sometimes it is nice to have access to the serial console. Although you wouldn’t want to dedicate a board to it it is perfect for occasional use. As a bonus, due to the flexibility of the FPGA’s I/O pins you can use it for multiple different I/O standards and voltages – If you change to IOSTANDARDs and maybe the Vco jumper you have also got yourself 2.5V or 1.2V CMOS to USB adapter!

Cool project, Mike.  It just so happens that we are now selling the pcDuino to compliment our own Gadget Factory product line-up, you can check it out in all its glory here.

(via Hamsterworks)

Indie Game ‘Meat Boy’ Cloned For Play On An FPGA

Wednesday, April 3rd, 2013

By way of Reddit, here is one college student’s project in which he recreates the awesome indie Flash game Meat Boy on an FPGA.

The FPGA Meat Boy creator, known only as “skipToThe3nd” used an Altera DE2 for the project.  Here is an excerpt from his Reddit thread (when skipToThe3nd was asked about his display engine for the game):

In general, the display engine waits for the Meat Boy’s next position, scrolls the window if necessary, then paints the frame via a VGA connection in the SXGA 60Hz protocol (

I used a built-in PLL to generate the 108MHz SXGA pixel clock from Altera DE2′s 27MHz clock.  The pixel clock also drives x/y-counters, which are useful for knowing what color to paint and also for partitioning SRAM ownership between the physics and display engines for their map-data reads (as the map is described 2-bits per 32×32 tile in SRAM).

Way cool to attempt such an ambitious game on your FPGA!  You can take a look at the source code for the project here.

For reference (and for fun!) here’s a link to the original Meat Boy game.  That’s essentially what he was aiming for.  It gives a sense of the crazy amount of work that must’ve gone into this dude’s project!

(via Reddit)