semi-simple
Beginner
(Not technically "Arcade", but it supports Superguns, so hopefully that's still on topic)
I wanted to introduce my open-source project, Backporch: https://github.com/semi-simple/backporch
I created this project to address one of my pet peeves: retro console cables can be difficult to source and expensive. Depending on one's need, it's can be typical to have 2 or 3 cables per console.
(Also many of them are not designed as proper transmissions lines with adequate impedance matching (i.e. it's common to have input resistors near the output, in the SCART connector)).
I wanted to create a board where all components can live that can then be connected with cables with no components inside to consoles and to displays.
The hope is that it would allow us to use high-quality but cheap, easily sourced cables. The components on the board itself can be very high quality.
As the project stands today, with no cost optimization and by using Oshpark and Digikey, the cost is about ~20$ per board.
My approach is as follow:
1. Standardize inputs as mini-din 9 and mini-din 8
- mini-din 9 follows the Mega-Drive/Genesis "standard" (i.e. impedance matching resistors and coupling caps are needed), TTL SYNC
- mini-din 8 follows the XRGB Mini / NES RGB "standard" (no impedance matching resistors nor coupling caps are needed), "75 Ohm" (~0.7V PtP) sync
2. Standardize outputs as mini DIN 8 (for SCART) and DE-15 ("VGA")
- Component-free Mini-DIN 8 to SCART cable are easily available. A simple Mini-DIN 8 cable can be used to connect to a Framemeister.
- DE-15 can be used to connect directly to the OSSC. High-quality and cheap DE-15 to BNC cables are widely available to connect to a PVM.
The board includes a sync stripper, so it's easy to use Luma, Green, or even composite as a sync source if needed.
Here are some passive cables that can be used with this board:
- Short, schielded mini DIN 9 to mini DIN 9.
- Short, schielded mini DIN 8 to mini DIN 8
- SCART (input) to mini DIN 8 (output)
- Mini DIN 8 (input) to SCART (output)
- DE-15 ("VGA") to BNC
- DE-15 ("VGA") to DE-15 ("VGA").
Many consoles can be connected by simply cutting a cheap cable and soldering a plug that will fit into that particular console. No components needed. (Refer to https://github.com/semi-simple/backporch for some examples, but a lot more can be done).
Mega-drive/Genesis, NES RGB and a few SuperGuns (HAS, Minigun) don't even require doing anything, grab the right cable and connect!
I hope you find this helpful. Please don't hesitate to ask questions, make comments or even request features / changes!
I wanted to introduce my open-source project, Backporch: https://github.com/semi-simple/backporch
I created this project to address one of my pet peeves: retro console cables can be difficult to source and expensive. Depending on one's need, it's can be typical to have 2 or 3 cables per console.
(Also many of them are not designed as proper transmissions lines with adequate impedance matching (i.e. it's common to have input resistors near the output, in the SCART connector)).
I wanted to create a board where all components can live that can then be connected with cables with no components inside to consoles and to displays.
The hope is that it would allow us to use high-quality but cheap, easily sourced cables. The components on the board itself can be very high quality.
As the project stands today, with no cost optimization and by using Oshpark and Digikey, the cost is about ~20$ per board.
My approach is as follow:
1. Standardize inputs as mini-din 9 and mini-din 8
- mini-din 9 follows the Mega-Drive/Genesis "standard" (i.e. impedance matching resistors and coupling caps are needed), TTL SYNC
- mini-din 8 follows the XRGB Mini / NES RGB "standard" (no impedance matching resistors nor coupling caps are needed), "75 Ohm" (~0.7V PtP) sync
2. Standardize outputs as mini DIN 8 (for SCART) and DE-15 ("VGA")
- Component-free Mini-DIN 8 to SCART cable are easily available. A simple Mini-DIN 8 cable can be used to connect to a Framemeister.
- DE-15 can be used to connect directly to the OSSC. High-quality and cheap DE-15 to BNC cables are widely available to connect to a PVM.
The board includes a sync stripper, so it's easy to use Luma, Green, or even composite as a sync source if needed.
Here are some passive cables that can be used with this board:
- Short, schielded mini DIN 9 to mini DIN 9.
- Short, schielded mini DIN 8 to mini DIN 8
- SCART (input) to mini DIN 8 (output)
- Mini DIN 8 (input) to SCART (output)
- DE-15 ("VGA") to BNC
- DE-15 ("VGA") to DE-15 ("VGA").
Many consoles can be connected by simply cutting a cheap cable and soldering a plug that will fit into that particular console. No components needed. (Refer to https://github.com/semi-simple/backporch for some examples, but a lot more can be done).
Mega-drive/Genesis, NES RGB and a few SuperGuns (HAS, Minigun) don't even require doing anything, grab the right cable and connect!
I hope you find this helpful. Please don't hesitate to ask questions, make comments or even request features / changes!
