RetroPie in a Dreamcast VMU!

moosepr

@obsidianspider I like how the vmu icon has appeared in your signature already! :P

obsidianspider

@moosepr Well, I ordered one already, (two actually) so it's as far along as the Burger King project that's in a box. ;) I'll start a thread for that once parts show up.

obsidianspider

@moosepr I can't seem to find the OLED display that was used on satri360's build, but the tfts I ordered from China were $4 each, so I think it's worth the experiment.

moosepr

@obsidianspider if you have ordered the 1.44 inch tft screens, you can actually remove it from the pcb and wire it direct

https://twitter.com/Pi0CKET/status/845405718303952896?s=15

moosepr

@obsidianspider His is the adafruit oled with the sd card

He seems to have trimmed the PCB down to save space

obsidianspider

@moosepr You read my mind, good sir. I actually thought of you when I was contemplating the attempt! If for no other reason than to figure out how to pin it and if fbtft would work. Watching some Greek and Russian YouTube videos about the screen lead me to learn that it's got an ILI9163 driver, so it should work with the latest incarnation of fbtft. An interesting note about those screens is in the code comments

/*

This display:

http://www.ebay.com/itm/Replace-Nokia-5110-LCD-1-44-Red-Serial-128X128-SPI-

Color-TFT-LCD-Display-Module-/271422122271

This particular display has a design error! The controller has 3 pins to

configure to constrain the memory and resolution to a fixed dimension (in

that case 128x128) but they leaved those pins configured for 128x160 so

there was several pixel memory addressing problems.

I solved by setup several parameters that dinamically fix the resolution as

needit so below the parameters for this display. If you have a strain or a

correct display (can happen with chinese) you can copy those parameters and

create setup for different displays.
*/

I really need to stay off the Internet at 2 AM when I can't sleep. At least I'm only into this project $20 so far. It'd only be $10 if I bought one of each, but I've learned my lesson on breaking stuff before…

moosepr

@obsidianspider well I was already a few weeks into my latest project when this one popped up.

I couldn't find the ili9163 driver when I was testing the other night, but the screen seems OK with the st7735 driver (apart from it trying to do 128x160 resolution)

obsidianspider

@moosepr Since it looks like you've already got some experience with that particular ILI9163 display would you be willing to share how you attached directly to the ribbon cable? The PCB has a resistor, capacitor, and something else that I can't quite identify, so I'm not sure what they're doing.

obsidianspider

@moosepr said in RetroPie in a Dreamcast VMU!:

already a few weeks into my latest project

I saw the teaser photos on Twitter. Now I'm curious what else you're up to. Your skill in making PCBs is something I would love to learn.

moosepr

Sure! You will need a 10ohm resistor to tame the backlight, and other than that, wire it straight to the pi!

The boards have a 3v regulator. I can't find an exact data sheet for the screen I have, but most indicate that the screen is OK with 3.3v

Here is the schematic for the little red board

alt text

Credits to https://www.google.co.uk/amp/s/chioszrobots.com/2014/08/30/1-44-red-serial-128x128-spi-color-tft-lcd-module-display-screen/amp/

moosepr

@obsidianspider said in RetroPie in a Dreamcast VMU!:

@moosepr said in RetroPie in a Dreamcast VMU!:

already a few weeks into my latest project

I saw the teaser photos on Twitter. Now I'm curious what else you're up to. Your skill in making PCBs is something I would love to learn.

Making the boards isn't that difficult really, the hardest part is getting the schematic electrically correct

obsidianspider

@moosepr A resistor I can handle. We'll see if I can solder on the ribbon cable without messing it up. I knew there was a reason I bought two. ;)

moosepr

@obsidianspider just be gentle with the heat and you will be fine. Tin the wire, flux the ribbon, and it will soon stick

edmaul69

@moosepr do you have a link on how to wire it directly?

Edit: Nm. The page didnt load all the posts. I see it now

ABrugsch

Hi. Checking in from the other vmu build thread on sudomod ;)
One of the pieces of my puzzle arrived which was a tiny charge/boost board. I'll be doing a bit more of mine soon,but will probably end up doing a custom pcb for it something like @moosepr's PiCB-tft board.

moosepr

just a dump of info for anyone venturing down this rabbithole. the screen will run as a st7735, but the driver is trying to do 128x160, so its not ideal!!

it will also run as an ili9163. the resolution is correct at 128x128, but the driver is behaving weird!! it technically runs upside down (chip at the top) and the rotation chops off some of the screen at 180 and 270

http://imgur.com/a/YRp66

if your interested, if you follow my guide in my signature, but replace the contents of

/etc/modprobe.d/fbtft.conf

with

options fbtft_device name=fb_ili9163 gpios=reset:25,dc:24 speed=40000000 bgr=1 rotate=0 custom=1 fps=60

then you will have a working screen!!!!!1

A Former User

Imagine if the VMU itself could be configured to be fit inside a Dreamcast controller and it would be able to recognize the controller.
Wouldn't that be cool?

edmaul69

@itsnitro since it doesnt have a select button on the controller you couldnt play super nintendo games. But you could play genesis games.

obsidianspider

@moosepr I think for the VMU having the cable come out the top will work better (0 rotation) anyway since the buttons will bump right against the screen. Here's an image of the VMU from a teardown on iFixit.

obsidianspider

I started a build thread to contain the discussion in one spot as I work on this.