retroGamePi - presenting my retro console project! - Page 1
Forum section: electronics / projects

author: ballanux
author_rank: Contributor
timestamp: April 12, 2017, 07:40:11 pm
content: Hi! Sorry for the long post, I will try to compensate it with some pretty photos at the endI have been working on a raspberry pi retro-console for around 1.5 years on my free time, I'm now on the second revision of the prototype and I would like to ask everybody's opinion on several points.First of all, my project is called "retroGamePi" and I haven't publicized it much for now, it differentiates from other similar projects like Adafruit's "piGrrl" in which this is a more complete solution, you don't have to make any cable connection between boards. So this should be easier for people who for example don't know to solder but still have some software/linux/raspberry pi skills.Right now I'm assembling 20 prototypes, some of them to gift to friends and some of them to gift or sell at cost (I haven't decided yet hot to proceed) so I can have some feedback on the good/bad points of the project.If everything goes well my goal would be to sell it as a kit. But here I would have several options:- Only sell the PCB, people should buy the raspberry and 3d print the enclosure: I could do that as soon as I polish the firmware. The investment required would be the smallest.- Sell the PCB and an injection molded enclosure: would be much nicer product, as printing the enclosure requires a lot of experience and hours, but for sure I would need to make some kind of crowdfunding campaign.- Provide everything needed, including the raspberry and the SD card: This is tricky, I don't know what is the policy on re-selling the raspberry pi, if there are reduced prices when you buy in quantity etc. Also, about the software... most of the software is GNU, if you distribute it, you should also make available a repository with all the source code, correct? I would like to avoid that. This would certainly increase the possible user base, I think it could be a nightmare to try to maintain all the software... In any case, only free/GNU software would be provided to the user, no ROMs, so if the user wants that, there are several online tutorialsThe enclosure was designed by me from the ground up, so the PCB and all the components fit nicely. Of course there is an inspiration on the GameBoy, but everything was done with just a few image references and to fit the raspberry and all the peripherals.Some more technical aspects:- Supports raspberry pi B+, 2, 3, zero and zero W- 3.2 inch LCD screen 320x240px, that is the maximum resolution with a good refresh rate- Amplified stereo sound by headphone and mono sound by integrated 0.5W speaker- 4 thumb buttons, 2 trigger buttons, start, select, volume up and down and power button- Analog thumb-stick- Resistive touchscreen- Accelerometer- Dual vibration motors for haptic feedback- Li-Po battery charger through micro USB. Tested with batteries from 1300 to 6600mAh, thermally and under/over voltage protected- USB serial port access to the raspberry pi console port- Access to the raspberry USB, Ethernet and HDMI ports, can be used on an HDMI screen- Custom enclosureAll inputs appear as a normal joystick so they can be used with any software. It's main intended use is with the retroPie compilation and emulationstation, but can be easily used for any custom or existing Linux game.As for the license of the hardware/firmware I will probably release/open it as soon as I make it into production or if I unfortunately decide to give up on any mass production... but for now I'm keeping it private.I was used to work with the typical industry tools, but for this project I used open source tools. KiCAD for the PCB, FreeCAD for the enclosure, QT Creator for some test programs and it is also my first time working on the Linux kernel (that was a tough one to learn). The only non open source tool is Atmel Studio... Any idea on which license could I release the firmware? I suppose it can't be GPL as I'm using the ASF libraries, but I'm no expert on that.I'm an electronics engineer and I design power electronics, specifically BLDC inverters, but I wanted to try to do some consumer electronics and learn to use several open source tools. I would be able to source and manufacture all the required components at my workplace, but I would be alone in the customer support department... Due to this, if I go for a crowdfunding campaign I'm thinking in crowdsupply. I bought from them the novena laptop and they handle any hardware replacement themselves and I'm also waiting to receive my EEZ-h24005 and that campaign seems to also be doing great!If I went into a crowdfunding campaign I would have to re-design the enclosure for injection molding, I haven't done that before... but this is why I'm doing the project, to learn new thingsEarly 3D render:First prototype:Assembled:It works!Test program made in Qt Creator:SD card and trigger detail:I made a custom reflow oven, I want to make 20 prototypes!KiCAD render feature is very nice!And to finish... this is my last board revision, I assembled it today and everything seems to be correct for now!Any questions/criticism are welcome!

author: 5321488
author_rank: Contributor
timestamp: April 13, 2017, 12:07:17 am
content: Looks sleek! Nice project

author: ballanux
author_rank: Contributor
timestamp: April 13, 2017, 10:51:36 am
content: Thanks! I'm very happy with the results and specially surprised on how well the reflow oven workedToday I made a little more testing and everything seems to work, I had special fear for some fine pitch components like the voltage regulators and the accelerometerNow I need to 3D print a new enclosure due to some mechanical changes from the old revision

author: timothyaag
author_rank: Contributor
timestamp: April 13, 2017, 05:01:04 pm
content: Wow, I love this idea. I would buy one if they were available.As this is portable, do you have any ballpark figures on the battery life while in use? And in that vein, have you done anything interesting to optimize for battery life? If I'm remembering correctly Raspberry Pi's can pull over 100 and sometimes over 200mA at idle, and that's without a screen and the rest to power.

author: ballanux
author_rank: Contributor
timestamp: April 13, 2017, 05:27:55 pm
content: Quote from: timothyaag on April 13, 2017, 05:01:04 pmThanks, is encouraging to hear that! I'm pushing to have it ready ASAPThe consumption is 600mA on average with the maximum setting both on the LCD backlight and the volume while playing a game, so that would mean from 10 to 11 hours of playtime with the bigger battery. Only the audio is 440mW so reducing the volume or using earphones could have a big impact. This was measured on a raspberry pi 3 with wifi and ethernet. Using a raspberry pi zero would reduce the consumption a lot, but I don't have any measurements right now. Anyway, I assume 600mA is the worst case.

author: RGB255_0_0
author_rank: Frequent Contributor
timestamp: April 13, 2017, 05:36:34 pm
content: This is the sort of thing that should be on Kickstarter. I'd certainly be interested!

author: ballanux
author_rank: Contributor
timestamp: April 13, 2017, 06:02:10 pm
content: Thanks! before any crowdfunding I have to figure out exactly my cost in quantities.If I want to make injection molding cases probably 1000 would be the bare minimum... but I'm not an expert on that, I have to consult with some colleagues and have at least an approximate quotation on the molds