Atom and Single Board retro-Computers

[gob33]

Im lauching a new idea: Who would be capable to install Atom on any FPGA ?
Cores for the BBC or the Electron and even the Archimedes can be found for the following boards but no Atom in sight.


The MiST FPGA card by Till Harbaum and Lotharek emulates many retro-systems but not the Atom.
It cost is ~215€ with a case.
It has already many cores defined (Atari,Amiga, Apple II,ZX Spectrum,...) and even for the BBC. See the wiki.
I think it should be fesable to build an advanced "Atom core" by reusing pieces of code from the other cores.
And why not emulating an advanced 6502 with large memory map, colors and BBC basic ?
The card/case is already available for anybody.

Specs:

• FPGA Altera Cyclone III EP3C25
  Micro-contrôleur ARM AT91SAM7S56 for input/output management.
  32 Mo SDRAM 16 bits.
  USB controller MAX3241E.
  USB hub TUSB2046.
  VGA connector analogic.
  4 USB ports host mode.
  Analog stereo output.
  Micro USB port for power (300 mA/5 V minimum and 400 mA/5 V with devices) and for flashing the microcontroller.
  SD card slot.
  Two DB9 ports for joysticks connection.
  Two MIDI ports.
  Three push buttons (reset the card, menu and the last one defined by the developer).
  On / Off switch.
  A jumper to activate flashing of the microcontroller via the micro USB port.
  Two DIP switches (for firmware or disabling the FPGA).
  ARM JTAG connector for development and debugging of the microcontroller.
  FPGA JTAG connector for development and debugging of the FPGA.
  ARM connector for debugging.

JTAG connectors are not present on commercial version (for devs only)

The above specifications are very interesting and normally allow re-implementation and enforcement of any machinery 16/32 bits.
They are better than the Minimig at memory and FPGA programming space. In the words of the designer of the project, the MIST card is powerful enough to enable the implementation of the Atari Mega STE at 16 MHz and the Amiga 1200 (AGA) to 28 MHz.

[hoglet]

Have you seen the current Atom FPGA project?
viewtopic.php?t=6313
https://github.com/hoglet67/AtomFpga

This currently supports several boards:
- Papilio One with Arcade Wing
- Papilio One with my own Wing
- Papilio Duo

You're welcome to have a go at adding Mist support.

Dave

[gob33]

Yes i have looked (not in deep details) at fpga projects.
Your work could be a starting point for adapting to another card more dedicated to retro-systems.
Mist board is more frequently used in retro-gamimg than a papillo board and you can use other different platforms/cores in same investment if not satisfied.

[gob33]

You should have a look at the ZX Uno, a FPGA spanish clone of the ZX Spectrum.
Project is free, schematics and PCB available to copy, adapt, transform.
This clone as many differents cores, specially BBC and Atom(VGA) ones.
They started from the Hoglet Atom core, remapped for their pins, new timing from their 50MHz oscillator, modified keyboard.

Specifications:

• FPGA Xilinx Spartan XC6SLX9-2TQG144C
  Static Memory 512Kb, AS7C34096A-10TIN
  50MHz Oscillator
  Superfo's 1 transistor EAR Circuit (one transistor)
  Composite video output using an AD724 with XTAL 4.43MHz / 3.58MHz for PAL/NTSC operation (user selectable)
  PS/2 keyboard
  RCA connector for composite video
  Stereo audio jack
  EAR jack connector
  Molex 1.25mm connectors for JTAG and RGB
  Slot for SD Cards
  Expansion port with 3 male pin strips
  Micro-USB power connector
  PCB Size: 86x56 mm. (Compatible with Raspberry Pi 1 cases although some machining with a dremel is needed).

The ZX-UNO also includes a boot time setup program (similar in appareance to most PC Setup BIOSes), from which the user can configure:

• Memory testing, EAR signal level testing, keyboard testing
  Silent Boot (no ZX-UNO logo at boot time)
  Spectrum keyboard implementation (issue 2 or 3)
  Machine timings (48k, 128k ..)
  Enable or disable contended memory
  Enable or disable DivMMC feature and/or DivMMC NMI trap
  Choose default ZX Spectrum to boot from, or choose default core (for other non-Spectrum machines)
  ZX Spectrum ROM manager (add, delete, update)
  Core manager (allows adding other machines' cores, up to 9 cores, without having to use an external JTAG programmer)

Facebook

Project page

Promotional Video

[gob33]

ZX-Uno should be available in September 2016, mounted, welded, tested and with the latest cores and firmware
at a price of ~72 EUR Paypal.
Most are already reserved by the crowfunding campaign.
The transparent enclosure is at ~12 EUR, the official black/white one is sold out after the crowd order.
Also needed:
- A special VGA cable (see spanish forum) ~12 EUR. The main video output is composite video but also accepts VGA and RGB.
- A standart 5V micro USB power supply 5V. Power consumption is about 80mA, so anyone is good
(smartphone charger, PC USB cable, TV USB cable).

Contact: Antonio Villena

ZX-Uno English Manual

[gob33]

For those who didnt take the crowdfunding campaign of the ZX-Uno team, there is now a new clone of the ZX-Uno 4.1, 100% compatible.
ZX-Uno's licence is free and permits anyone to commercialy copy/adapt the product.
Their plate is larger and has the DB15 VGA connector instead. Price: 100 €

www.8bits4ever.net/

Modifications from official ZX-UNO 4.1:

-Board dimension changed to 100mm x 80mm
-Various components moved to different positions

-Replaced all 0603 passive components with 0805 counterparts
-Replaced diodes with sot23 counterparts
-Replaced microJST JTAG connector with 2,54mm pitch, single pin row connector
-Replaced microJST Video connector with DB15 VGA connector
-Replaced audio output 3,5mm jack with two RCA jacks
-Added power jack connector
-Added power button, digital switch circuit and LED
-Added reset button

[gob33]

2 new non-official updates of the ZX-Uno 4.1 running Atom and BBC software.

1) v4.2 by Antonio Villena

Memory upgraded to 2Mb.The raspberry case is from Cyntech.
Shop - Forum thread

2) VGA + 2Mb by Manuel Fernández
Extension port removed + 2 joysticks.

Forum Thread - Video

[gob33]

http://www.8bits4ever.net has released their own clone of the Mist.
It is less expensive (160€ versus 220€) but also has less ports (2 USB, 1 DB9). The case is 3D printed.
As for the Mist, it runs a BBC core but not an Atom (to be written by someone).
Note the new Mist has now MIDI integrated.

[gob33]

A new interesting projet: MiSTer by developper sorgelig.
Basicely, it's MiST ported to Terasic DE10-nano board with a 4x larger FPGA (110K LE) and faster ARM (800MHz).
Board is mass produced by a big manufacture and freely available for a relatively cheap price.
The MisTer Project with the correct CORES turns the De10-Nano board into multi console FPGA emulation
MiSTer adds several daughter boards (SDRAM, I/O, Real Time Clock, USB) to the original DE10-nano board.
All cores can be ported.

Wiki - Video - Announce

[waltermixxx]

I am currently using the ZX-UNO as an acorn atom. It works very well.
I bought it specifically for the acorn atom core. I may try and 3D print some kind of Acorn Atom'ish case for it. I do miss my old acorn atom. Having this may be closest I come to having one again. Thanks Hoglet for the fpga core.

Totally awesome.

I may still try and build one from scratch.
I have all the chips. I would most likely wire wrap it instead of point to point. That worked great for my wire wrapped cosmac VIP redo (32k instead of 4, and 32k rom preloaded with software that gets moved to 0x200 depending on which key is pressed during reset.

Thanks again folks who helped make the atom on the ZX-UNO possible.

[hoglet]

Thanks Hoglet for the fpga core.

You are most welcome!

[gob33]

MISTICA FPGA16 is the name of a new 100% compatible Mist board (although without MIDI or JTAG connector) designed by ManuFerHi (Spain).
No Atom core here yet but a BBC core exists.

The biggest advantages over the original Mist are the new audio and video connectors and the lowest price (~169 EUR vs 215 EUR for a Mist), while maintaining full compatibility with the cores developed for Mist. Its power consumption is very low: about 250mA in the cores menu and about 340mA using the friend's core.
Like the Mist, one of the recommended controls for is the clone version of the Super Nintendo, brand Buffalo Classic, quite good and at an affordable price.

It should be noted the high quality of the image produced through the RGB output on a CRT television, greater than the original machine through the RF signal.

Characteristics:

• 100% compatible with Mist and its official cores
• Composite video output
• Audio output by RCA and stereo jack
• DIN9 output for RGB scart with the same cable as the ZX GO +
• SVideo Exit
• EAR input usable by some cores such as Spectrum
• The main cores (almost all) are adapted to 15khz with what they work in CRT televisions
• Power via MicroUSB with mobile charger or 5V Jack

Where to buy a MISTICA FPGA16 ?

The best thing is to speak directly with ManuFerHi , who is its creator ... with a little luck you will be in time to acquire one of the first ones or participate in future editions. It is a product with an impeccable finish and a fairly low price compared to the original Mist, today € 169 including shipping to Spain and acrylic housing.
Note (20181014): You can buy it on ebay.

Links:

Mist Board Wiki
List of cores supported by MiST / MISTICA and MiSTER
Mist Board Github
MiST Forum on Atari-forum.com
Testing the MISTICA FPGA16
MiST Board Issues
MiST vs MISTICA FPGA16 in RetroWiki
Video presentation of MISTICA FPGA16
MIST & MISTICA + Cores Wiki

Alternative repositories

https://github.com/Gehstock
https://github.com/robinsonb5
https://github.com/rkrajnc
https://github.com/sorgelig
https://github.com/wsoltys
http://ssh.scrameta.net/

[gob33]

Seems the production of the original Mist is stopped due to the cheaper clones.
They finish their stock.
Read: The last Mist

[crj]

That sort of thing is a big problem.

I'm currently in the early stages of working on a product. If I pull it off, it'll be a lot of effort, therefore expense. I really need to recover my costs, and if it's a success then being modestly rewarded for my pains would also be nice.

It would be really nice to keep everything open, so anybody who wants to can hack on it, improve things, turn what I've done into something I never even imagined. But it would also be really nice if nobody straight-up copied what I'd done and sold it more cheaply.

It's hard to see a solution to that dilemma. Maybe fund development via Patreon and let manufacturers compete? I dunno.

[gob33]

Seems there is a MIST - MISTICA core for Atom /Electron here (VGA only).

[hoglet]

Seems there is a MIST - MISTICA core for Atom /Electron here (VGA only).

I believe this is just the Acorn Electron (incorrectly named the Atom Electron). There is no Atom stuff there at all.

It makes use of my Acorn Electron FPGA core.
https://github.com/Gehstock/Mist_FPGA/b ... a_core.vhd

Dave

[gob33]

I think it should be possible to use the new Amiga FPGA Vampire v4 as a standalone platform for an Atom / BBC evolution.
The card implements a virtual 68080 @ 93 Mhz named "Appolo Core" and all is done in the Altera Cyclone V FPGA so reprogrammable.
Inputs / outputs are rather complete. 512 Mo DDR3. No need to conceive an Acorn dedicated specific PCB.
You could even put an Atari on it, faster than the FireBee.

The case could be the small metalic case or the Checkmate compatible case.

[roland]

That's a nice board that probably can do an Atom. Personally I see two disadvantages:

1. It's not Xilinx based so I should need to buy/build another development environment (some people might call this an advantage)
2. More important (at least for me) is that some Atom I/O is still missing like the Atom I/O bus, cassette interface, audio (?), serial and tube

But I also see some advantages: it might be possible to use the I/O headers to hook up a real Atom keyboard, it's compact but fully equipped compared to the Pizza FPGA board that I use for my FPGAtom (which is still my favorite Atom based FPGA because of the many I/O ports).

Thanks for sharing!

[hoglet]

I'm less concerned about it not being Xilinx based, as we already have stable Altera DE1 ports of Atom FPGA and Beeb FPGA.

But unfortunately this board uses DDR3 SDRAM (rather than SRAM) which will mean alot of rework, if it's possible at all.

Sorry, but I'm not interested in supporting this.

Dave

Edit: And it also seems rather pricey!

[janrinze]

On the side of cheap FPGA based systems:

The UP5K has plenty LUT and memory to have a full Acorn Atom.
For example the upduino2.



5K LUT
128KB SPRAM

The chip is a 48 pin FPGA.

Since there is already a port to the ICE40 HX8K it should be trivial to get it running on this board.
The board costs around 10 euros.

[janrinze]

I did a quick port of my miniatom to the up5k board.
The 6502 cpu can run up to around 18 MHz and the vga circuit up to 28 MHz.

Currently I have PS/2 keyboard and VGA out (RGB 3:3:3).
Main memory is 64KB SPRAM, the video ram is DPRAM allowing to be a shadow copy.
I will try to see if SDDOS works.

The upduino v2 is not well designed and has clock instabilities. To fix that I added some capacitors over the 3.3v and 1.8v regulators.

I wonder if it is easy to design a small board with vga, dual ps/2, sdcard and audio out.

[janrinze]

Using the up5k evb board from Lattice i have clean video output and SDDOS working too.

So in short: the lattice up5k is capable of housing a full Acorn ATOM with sufficient I/O and memory.

That means:
- it is possible to have all logic and RAM in one chip costing only 6.70 euro's.
- There is 39 I/O pins available and it will require a serial flash chip for configuration and ROMs.
- Can be programmed using open source tools Yosys and Nextpnr.
- Allows for a CPU clock up to 18 MHz.
- should be possible to create a PCB with all components for around 30 euros.

[gob33]

-- Moved --

[janrinze]

https://github.com/joshajohnson/iCE40-feather

I'm trying to see if it's possible to get a cheap platform for ATOM FPGA tinkering.

I already have been able to run it on:
- up5k breakout board from lattice. (128KB internal SRAM)
- HX8K breakout board from lattice (there is a SRAM extension board design for this : https://github.com/maikmerten/hx8k-breakout-extension )
- Upduino v2.0 ( up5k based but has unstable clock frequency issues causing wobbly jitter in VGA)
- icoBoard ( has 1MB SRAM @ 10 ns and 4 PMOD. I have the ATOM keyboard connected directly to this board.)
- BlackIce II ( Hoglet has a full implementation on GitHub.)

VGA output with PmodVGA (Diligent)
HDMI output with PMOD from 1bitsquared ( I have 1280x720 stable output.)

[Volhout]

Using the up5k evb board from Lattice i have clean video output and SDDOS working too.

So in short: the lattice up5k is capable of housing a full Acorn ATOM with sufficient I/O and memory.

That means:
- it is possible to have all logic and RAM in one chip costing only 6.70 euro's.
- There is 39 I/O pins available and it will require a serial flash chip for configuration and ROMs.
- Can be programmed using open source tools Yosys and Nextpnr.
- Allows for a CPU clock up to 18 MHz.
- should be possible to create a PCB with all components for around 30 euros.

Sound interesting. 39 pins will require external hw of you want to support pl6 and pl8...

[acory]

- up5k breakout board from lattice. (128KB internal SRAM)
- HX8K breakout board from lattice (there is a SRAM extension board design for this : https://github.com/maikmerten/hx8k-breakout-extension )
- Upduino v2.0 ( up5k based but has unstable clock frequency issues causing wobbly jitter in VGA)
- icoBoard ( has 1MB SRAM @ 10 ns and 4 PMOD. I have the ATOM keyboard connected directly to this board.)
- BlackIce II ( Hoglet has a full implementation on GitHub.)

I had a quick google and couldn't find anywhere obvious to buy these boards from in the UK. Any suggestions or indications of cost?

I am aware that the Lattice chips have their own open source tool chain, my question is - "what is wrong with the Lattice tool chain?".

regards...

--acory

[gob33]

ManuFerhi (Spain) has launched a new version of its Mistica FPGA 16 called the "SIDI FPGA".
It is compatible with all cores of Mist / Mistica but at the lower price of 99 EUR !!

Main Components:

• Altera Cyclone IV EP4CE22 FPGA
• 256 Megabytes 16 bit SDRAM
• AT91SAM7S56 ARM IO controller
• MAX3421E USB host controller
• TUSB2046 USB HUB

External Connectors, buttons and LEDs:

• 4 USB host ports
• Analog VGA output with 3*6 bits colour depth
• Analog DIN9 RGB output with 3*6 bits colour depth
• Stereo analog audio output
• Audio input for tape loading
• Micro USB for Power Supply and IO Controller flash update
• 2.1x5.5mm barrel plug for power supply
• MicroSD Card slot
• 3 LEDs (Power, FPGA and IO Controller)
• Reset button
• Power Switch

Internal Connectors, switches and jumpers:

• 1 Flash Jumper for IO Controller flash update via Micro USB
• FPGA JTAG connector for FPGA development and debugging
• FPGA Expansion connector for MIDI/RS232/Debugging/...

Wiki
Store

Mistica vs Sidi video by

Sidi in action (35min)

[gob33]

Piotr Gozdur (Poland) has created a small "Do It Yourself" FPGA board for retro computing.
It runs Amiga, Spectrum, NES cores.

Specs for the DIY-A586 board are:

• FPGA Spartan6 XC6SLX9 (same as ZX-Uno)
• 8MB 16-bit SDRAM memory (huge !)
• 16MB flash for core and ROMs
• HDMI output
• analog audio output + tape deck input
• SD slot
• RS232
• 2 x joystick port
• 2 x PS / 2
• A500 keyboard connector
• floppy disk drive connectors
• 2 buttons (menu and reset)
• 2 LEDs
• 5V USB-C power socket
• Dimensions 100x100mm

Interesting, it has a tape input, a RS232 and a 80186 core for DOS progs.

Presentation elektroda.pl
Github files: Diagram, gerber, cores, bill of materials

[-B-]

The ZX Spectrum Next has an Atom Core too (photo stolen from Facebook)....

[hoglet]

The ZX Spectrum Next has an Atom Core too (photo stolen from Facebook)....

Is there any more information available on this core?