Pi2Scart 15khz 240p with a Philips PAL Tv

I have set up Scart out on my Philips 28" TV with Pi2Scart and this is a tricky one to call. The interface worked perfectly, although the Pi can no longer be seated in the Picade enclosure (in fact it will require some work just to get the door to close).

The default parameters worked perfectly;

  disable_audio_dither=1
  dtparam=audio=on
  dtoverlay=vga666
  enable_dpi_lcd=1
  display_default_lcd=1
  dpi_group=2
  dpi_mode=87
  hdmi_timings=320 1 16 30 34 240 1 2 3 22 0 0 0 60 0 6400000 1

And I played around with some optimal output resolutions from pi2jamma

    1600x240

but in the end I got best results from letting libretro output the native resolution with some black bars on most games.

The picture is now a lot more stable (you can see some of the flicker in the composite screenshot) and the colours are more vibrant. However games higher than 240p look clipped and the Emulation Station interface is tricky to use at the lower resolution.

The best of both worlds would probably involve having a separate Pi+Pi2Scart for Mame games up to the 1990s. Anything after Neo Geo would probably be better, even with flickery composite.

pi2scart Pi2Scart

compositeComposite

You can open the images in a new tab if you want to zoom in. The pictures were taken with auto focus and exposure, so they're not 100% accurate.

ReactVR at Dogpatch

I gave a lightning talk at DublinJS yesterday, accompanied by a live ReactVR demo. There were some great talks on VueJs and React, plus some good tech demos - I particularly liked the hacked Daydream controller.

My slides are here and you can clone and run the demo in your browser here.

The tech is already very stable but geometry requires a lot of optimisation and you'll need to use technques like texture baking to get a fast enough experience for users with headsets.

ReactVR Demo

ReactVR Demo

Dark Room Christmas Screening

Thanks to everyone who came, I hope you enjoyed the films. The screenings were;

  • 10pm - Electronic Voice Projection (16mm) [2016]
  • 10:20pm - The Inheritance (16mm) [2016]
  • 10:40pm - The Picture in the House (Super 8mm) [2012]

Setting up the room Testing sound and projectors Tim introduces The Inheritance The projection booth Lights down Mulled wine with Fr Tim Showtime Electronic Voice Phenomenon

Horror on North Brunswick Street this Saturday!

Come and see some short horror films this weekend - bring a few beers and enjoy a mixture of 8mm and 16mm stories. Both main features are shot in black and white on spring-driven cameras and developed by hand.

All films were shot and developed with the assistance of Dark Room and their amazing 16mm workshop.

The first is 'Electronic Voice Phenomenon' - delving into the clash of religion and science in Ireland, this film hones in on a period of detente in the 1970s when priests and engineers joined forces to record voices of the dead.

The violent, amateur photographic development process adds weight to the spectral presence in this spine-tingling film, as our heroes face down forces of evil and the outcome is uncertain as the malevolent power builds to a crescendo.

The second feature 'The Inheritance' follows the hapless relative of a deceased country landowner who discovers that his estate is not the windfall it appears to be. Featuring Tim Hawkin's inimitable direction, the film uses the results of some interesting research into apotropaic magic to uncanny ends.

I will also be screening an 8mm version of 'The Picture in the House' the infamous HP Lovecraft short story adapted for an Irish location, and perhaps some other spooky films will follow before the night is out.

Bet that trailer audio has already set your teeth on edge!

Horror on Brunswick Street

Picade Console

I had some free time this weekend so I took out the Picade kit I have been saving and finally assembled my new console. This is my third Raspberry Pi project, so setting up the linux installation was no problem, however the wire loom was another kettle of fish.

Luckily the Pimoroni guide includes a colour-coded wiring diagram which takes some of the pain out of the process.

wiring

I wanted a JAMMA cabinet like most people who grew up when the arcades were still around; then I looked at custom Mame cabs and finally I had to settle for a more pragmatic solution. The Picade is small and runs off a 2.5A@5V phone charger but it has a proper stick and buttons and feels rugged enough to hammer it like a real arcade machine.

The case is solid and all the parts are carefully prepared and labelled. All you need are a Philips-head screwdriver (I used the one on my penknife), a small flat-headed screwdriver, a Bluetooth keyboard (I use this Logitech one for all Raspberry Pi projects) and a HDMI-connected monitor.

guts of the machine

The console is a little tight on space but the parts are so well designed you could probably do it without the guide. Definitely something that is pleasant to put together with a beer in hand.

unshielded noise

I ran into some problems with speaker interference, so best keep the USB and speaker cables apart (see circled cables above). Also, the guide doesn't really cover the Raspberry Pi installation, so make sure that you hook up the 3.5mm jacks on the Pi and Picade board as well as USB.

finished article

This is the box when finished. There were a number of glue-backed rubber tabs, four thick black ones are obviously feet for the unit but the others I couldn't figure out - maybe they sit between the PCBs and the chassis? Make sure you don't screw the Pi or Picade board down too tightly - they will warp as they do not have flat bottoms.

You can test the buttons when you power on the unit. Each one will activate the Tx LED on the Picade board. Don't worry about the volume buttons - they don't trigger the light. The default wiring diagram assigns volume to the two black buttons on the front of the unit. I would probably change this to have the buttons at the side if I open it up again.

I also tried the top panel flipped in a left-handed position. This actually works pretty well but I discovered that I am now much more comfortable with a right-hand joystick layout and I wanted the printed flyer, so I flipped it back.

In terms of setting up the OS - I pulled down the latest RetroPie image. Once that had finished setting up, I plugged in the Bluetooth dongle and installed Unrar and Transmission.

sudo apt-get install unrar-free  
sudo apt-get install transmission-daemon transmission-common transmission-cli  

I also updated the Pi config to reduce speaker noise

sudo nano /boot/config.txt  

and add the line

disable_audio_dither=1  

The MAME Roms that RetroPie uses are now available from archive.org and can be installed with

cd ~  
wget https://archive.org/download/Mame0.37b5RomsAndBios/mame%200.37b5%20roms%20and%20bios.rar  
cd ~/RetroPie/roms/mame-mame4all  
unrar ~/mame%200.37b5%20roms%20and%20bios.rar  

The rest you'll have to look up and download with Transmission.

There's a lot of faffing about with configuring the inputs in Emulation Station that I'm not entirely finished with, but my final change will be to switch the input over to my old CRT TV for a more arcade-like experience. That can be accomplished with the following steps;

/opt/vc/bin/tvservice -o
/opt/vc/bin/tvservice -c "PAL 4:3"
sudo nano /boot/config.txt  

and add

sdtv_mode=2  

Overclocking to follow!