Smaller. Bigger. Better. SX-2

Smaller. Bigger. Better. SX-2

by hamlet on 02-04-2021, 08:29
Topic: Hardware
Tags: 8bits4ever, FPGA, SX-2
Languages:

The SX2, future-proof MSX FPGA for the years to come.

The SX2 is compatible with Victor Trucco's SMX firmware. In fact the SX2 can actually run the SMX stock binary out of the box. The firmware is being actively updated and maintained by KdL and he has kindly made a variant specifically for the SX2.

The hardware is also similar to the SMX, however things like power supply, the cartridge bus and the audio output have been reworked and hopefully improved stability and compatibility. The main difference with the SMX is that 8bits4ever produces the core and the I/O boards ourselves (unlike the SMX that uses a discontinued 3rd party core board). This gives them flexibility for further improving the design (perhaps to put and even bigger FPGA in the future) and also the ability to produce it as long and as much as we like to.

The main feature of the new SX2 is of course its FPGA. The Cyclone IV holds 22k logic cells (almost double than the old Cyclone I found on the OneChipMSX, Zemmix and SX1 boards), effectively opening the door for extending the OCM firmware with new features or even creating new firmwares.

Main Specs:

  • Altera Cyclone EP4CE22F17 FPGA (22K cells)
  • 32MB SDRAM
  • 3x expansion slots (2 standard, 1 through IDC connector)
  • 1x microSD card slot (FAT-16 support only)
  • D-Sub 15 VGA/RGB video output w/ scanline generator
  • Internal PSG, SCC+, OPLL (YM2413), OPL (YM3526), OPL2 (YM3812) and OPL3 (YMF262)
  • 3.5mm jack stereo audio output
  • 3.5mm jack tape in/out
  • PS2 keyboard port
  • PS2 mouse port (emulates MSX mouse on joystick port 1)
  • 2x DB9 joystick port (MSX standard)
  • Dual power supply connector (DC barrel type and mini USB)
  • Optional internal WiFi module (Requires SDBIOS)
  • MIDI out (through joystick 2 port)
  • 2/4 MB RAM mapper
  • Internal 1MB MEGASCC+/MegaRAM
  • 2 Turbo CPU modes: 5.37 or 8.06 MHz
  • Dual BIOS

The price is 160 € plus shipping from Spain for one unit.

8bits4ever would like to take the opportunity to publicly thanks KdL for all the support, testing and feedback and of course for his continuous work on the OCM firmware.

Relevant link: Homepage and infos
Updated specs 05/04/2021

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Comments (37)

By hamlet

Scribe (3721)

hamlet's picture

02-04-2021, 14:15

I see there is the HDMI connector missing, which made the SM-X very special.

By erpirao

Paragon (1230)

erpirao's picture

02-04-2021, 14:18

interesting, but i have two questions:
1.- inherits the lack of sound-in in the slot?
2.- Is msx-audio a complete compilation? Does it include adpcm, or is it using opl3 in emulation mode, because the msx-audio specification requires adpcm.
22kle, they are enough, to see if there is luck and the v9990 enters, I doubt that the opl4 will enter

By rolandve

Master (254)

rolandve's picture

02-04-2021, 14:59

April fools day?
The launch date of this message is mmm, somewhat suspicious. It also contains the scan line gimmick that breaks down video quality. No HDMI either. VGA starts to dissapear, D-scart is hard to find on modern TV's so FPGA builders hanging on too video outputs that can no longer be connected are in a somewhat uncertain position.

If they have got so much space left: why stick with MSX2+ and not TurboR?

By bsittler

Master (246)

bsittler's picture

02-04-2021, 19:02

This is really interesting! I have many questions:
- Are the audio expansions implemented inside the FPGA, or with actual Yamaha IC's?
- What's the price of the optional Wi-Fi module? Is it a readily available module or specific to this computer design?
- Is the IDC-to-cartridge adapter a standard one, and what is its cost?
- Are data pins on the mini USB port connected to the FPGA to allow future connectivity? If so, can it be used for data while using the barrel connector for (separate) power?
- Does it have physical configuration DIP switches? If so, can they be adjusted without removing the case?
- What fraction of the FPGA's resources are used by the current firmware, and is the unused portion sufficient that an R800 CPU core might be feasible in future firmware, provided someone writes one?

edit: also the shop says "Out of Stock / Release: First week April 2021" - does it mean the first batch sold out already, or are we still early?

edit 2: more questions somehow omitted from my first batch:

Also, can the VGA-style connector generate 31 kHz RGBHV (e.g. 480p VGA)? Can it generate 15 kHz RGBS? Can it generate S-Video? Can it generate composite NTSC (or PAL) video? Are any of the pins of the connector available for audio output? Does the current firmware support both 50 Hz and 60 Hz refresh rates? If any of the non-VGA signals are possible, will adapters or cables be available for their connectors? Would such signal pin usage on the connector match either previous OCM or V9990 designs?

Does this hardware design have any provisions for a battery-backed real-time clock? If so, could it be added in a firmware update or would it also require a board revision?

Are there any IO pins of the FPGA still available? If so, are they exposed internally by some kind of connector, and are there enough to consider future printer port and/or dedicated MIDI ports as expansions?

Has the audio output been recorded? How's the audio and video signal quality e.g. during microSD access?

Has RFI been measured? Is this a design that could benefit from metal shielding?

Has the temperature while operating been measured? Will it be needing additional heat sink(s) or fan(s) during long-term continuous operation?

edit 3: also, what does the default slot map look like with current firmware? Does it have hot-key toggling of slot assignments (internal vs. physical/external) for the hardware slots?

Is the scanline toggle button one that could be repurposed in the future for CPU mode toggling?

Are there any status/notification LED's? If so, are they external visible through the case window or otherwise?

Is there any electrical conflict when an MSX joystick is connected to port 2 and a mouse is also connected to the PS/2 port? Or can those usages be toggled in software/by keyboard keys?

Can the PS/2 ports source sufficient power for an active conversion adapter so that more modern USB peripherals can be used with this? In the SX-1 mini+ I use this one for the keyboard and connect a Logitech unifying receiver wireless keyboard dongle to it: https://www.amazon.com/Adder-KVM-konverter-USB-KMU2P/dp/B005... (I use it with this keyboard wirelessly: https://www.amazon.com/Logitech-Advanced-Wireless-Illuminate... )

edit 4: does the firmware support Kanji and kana input? If so, does it support Romaji conversion? Does it support either of the common MSX kana physical keyboard layouts? Will this work with a Japanese PS/2 keyboard?

Does the firmware support Hangul input? Does it support Hanja conversions? Will this work with a Korean PS/2 keyboard?

Does the firmware support Cyrillic input? Will this work with a Russian JCUKEN PS/2 keyboard?

Which other PS/2 keyboard layouts will work? US QWERTY? UK? French AZERTY? German QWERTZ?

Will changing keyboard layouts be possible at runtime, or will it require firmware replacement?

Are there any free I/O pins for future USB (MSX-USB?) peripheral support? What about for digital audio and/or video output? What about for analogue video input for digitization and/or overlaying? Audio line input? Light pen? If so, is there any internal connector exposing these pins, or would a board revision be needed?

Could a V9990 implementation possibly fit into this FPGA in the future, maybe with keyboard toggling of the selected video signal?

edit 5: will it work with Spanish PS/2 keyboards? What about Brazilian Portuguese ones?

Will it support Arabic input/keyboards?

edit 6 (last! I will rest): does it allow BIOS substitution from a file on the microSD (OCM SD BIOS feature) like the previous SX-1 Mini+? If so, can the same BIOS be used for both models or are they incompatible? And can the boot logo be replaced in this way too, for instance to customize the color?

By Sebbeug

Champion (320)

Sebbeug's picture

02-04-2021, 19:12

For someone who's following MSX's FPGA works, all previous questions are already known... (Hra, KdL, etc.)
@rolandve : Please respect this work and stop trolling.

It's a really nice piece of hardware...waiting for mine.

Thanks 8bits4ever Wink

By bsittler

Master (246)

bsittler's picture

02-04-2021, 19:51

Yeah, most answers seem known if it's the same feature set as previous OCM or SM-X, but I saw the word "most" and wondered if some of those were sacrificed in the new design, and also I see it is a new FPGA and wonder if it makes more capabilities possible. Also can't tell whether it's the same architecture as SM-X or just similar, and didn't want to assume all answers being identical

By rolandve

Master (254)

rolandve's picture

02-04-2021, 19:56

Sebbeug wrote:

@rolandve : Please respect this work and stop trolling.

Thanks 8bits4ever Wink

I've got some 8bit4ever products and I support their line of business.
@Sebbeug, I don't agree with your definition of trolling.

By bsittler

Master (246)

bsittler's picture

02-04-2021, 20:42

I think the concern about missing VGA and SCART inputs on recent monitors is a valid one, fortunately though some cheap but capable converters exist. I'm happy to pay a bit for a converter so that 8bits4ever doesn't have to purchase an HDMI license and pay a royalty for every unit even when some buyers won't use the feature. I hope this one will work with SX2: https://www.amazon.com/dp/B07121Y1Z3

I suspect the scanline simulation can be toggled/is optional. In any case it's not a gimmick so much as a simulation on VGA monitors of the appearance on RGB monitors, and might be especially useful when the video mode is interlaced, for example in KID. It trades off the blocky pixel effect from scan doubling for a brightness reduction and larger visible gaps, but I suspect it will look pretty good on a VGA CRT

By rolandve

Master (254)

rolandve's picture

02-04-2021, 20:51

bsittler wrote:

I think the concern about missing VGA and SCART inputs on recent monitors is a valid one, fortunately though some cheap but capable converters exist. I'm happy to pay a bit for a converter so that 8bits4ever doesn't have to purchase an HDMI license and pay a royalty for every unit even when some buyers won't use the feature. I hope this one will work with SX2: https://www.amazon.com/dp/B07121Y1Z3

I suspect the scanline simulation can be toggled/is optional. In any case it's not a gimmick so much as a simulation on VGA monitors of the appearance on RGB monitors, and might be especially useful when the video mode is interlaced, for example in KID. It trades off the blocky pixel effect from scan doubling for a brightness reduction and larger visible gaps, but I suspect it will look pretty good on a VGA CRT

In the amiga world, the Vampire designers have worked around the HDMI license. Just a noob question: is this compatible enough to replace my MSX2+ NMS 8250?

By hamlet

Scribe (3721)

hamlet's picture

02-04-2021, 20:52

I like to mention that the price for the SX-M is double the price for the SX-2 and that did't include shipping and customs fees. So fair enough to buy an adapter for a HDMI monitor by yourself of course.
I don't think USB input devices can be used that quickly, but there are still many cheap PS/2 versions available.

By bsittler

Master (246)

bsittler's picture

02-04-2021, 21:00

Is Vampire actually HDMI (with audio) output, or just DVI with HDMI pinout? I know many monitors and TV's won't play audio from a DVI source signal since it isn't part of the spec

By rolandve

Master (254)

rolandve's picture

02-04-2021, 22:28

I believe they ended up with DVI on HDMI pins. I'm still waiting for my Vampire 1200 so can't answer for sure, but the audio specifications say yes. The vampire manuals confirm mixed audio not being a part of the spec.

By gdx

Enlighted (4810)

gdx's picture

03-04-2021, 02:18

I would have preferred HDMI and USB for a new OCM but the price is very affordable.

By 8bits4ever

Resident (51)

8bits4ever's picture

03-04-2021, 10:57

Hello people!

We see there is many questions... difficult to answer all. The most recurrent seems to be about USB and HDMI.

USB will likely require a separate chip implementing the USB bus interface. For example, in the case of the MiST FPGA , it uses 3 chips (one of them is an ARM micro) working alongside the FPGA to implement USB bus, on screen menu, SPI, etc.
This not only would increase the price but also would require a major firmware redesign.

About HDMI, we had it on our prototypes and the compatibility was terrible (none of the 4 screens we have in our workshop were able to catch the signal). This is again a firmware level problem that could be improved in the future, but the fact is, when you can buy a highly compatible VGA-HDMI adapter for 5 bucks it does not make sense to spend time getting the on-board HDMI output to work.

By AxelStone

Prophet (3057)

AxelStone's picture

03-04-2021, 12:52

I agree, HDMI output is not interesting, at least from my point of view. VGA output is much more interesting for MSX FPGA since you can use as VGA and also as Scart. Also VGA output provides 0 lag, not like HDMI which has lag.

About USB support, it should be really nice to have it in the future. For example, should be possible to have a expansion board attached to 3rd slot with a USB controller and USB ports?

Thanks.

By psxdev

Resident (45)

psxdev's picture

03-04-2021, 15:10

8bits4ever wrote:

Hello people!

We see there is many questions... difficult to answer all. The most recurrent seems to be about USB and HDMI.

USB will likely require a separate chip implementing the USB bus interface. For example, in the case of the MiST FPGA , it uses 3 chips (one of them is an ARM micro) working alongside the FPGA to implement USB bus, on screen menu, SPI, etc.
This not only would increase the price but also would require a major firmware redesign.

About HDMI, we had it on our prototypes and the compatibility was terrible (none of the 4 screens we have in our workshop were able to catch the signal). This is again a firmware level problem that could be improved in the future, but the fact is, when you can buy a highly compatible VGA-HDMI adapter for 5 bucks it does not make sense to spend time getting the on-board HDMI output to work.

Did you think about an omega like design incorporating keyboard and some extras like ours old msx models all in one integrated the same case?

By bsittler

Master (246)

bsittler's picture

04-04-2021, 02:26

bsittler wrote:

I think the concern about missing VGA and SCART inputs on recent monitors is a valid one, fortunately though some cheap but capable converters exist. I'm happy to pay a bit for a converter so that 8bits4ever doesn't have to purchase an HDMI license and pay a royalty for every unit even when some buyers won't use the feature. I hope this one will work with SX2: https://www.amazon.com/dp/B07121Y1Z3

By the way I just tried this adapter with SX-1 Mini+ in VGA (31 kHz) mode and although it's not perfect (different pixel columns get scaled somewhat unevenly) it does at least faithfully reproduce both 50 Hz and 60 Hz resolutions in both progressive scan and interlaced signals, and the sound seems fine too. The color tint is unfortunately not quite perfect (and can't be adjusted that I know of) but surely is at least usable at least for gaming and programming

Given this I believe it will likely work fine for SX|2 also but of course I have not tested that combination

edit: color tint is fine actually, I just had a loosely seated connector at first

By hamlet

Scribe (3721)

hamlet's picture

05-04-2021, 18:52

Received a mail today from 8bits4ever that the preorder is open for the first batch. So don't miss this oportunity to get your SX-2!

Uodate:
And it seems to be already finished. The first batch for 20 units is closed.
Hope to see the next batch will be produced soon!

By Thom

Paladin (685)

Thom's picture

05-04-2021, 19:22

hamlet wrote:

Received a mail today from 8bits4ever that the preorder is open for the first batch. So don't miss this oportunity to get your SX-2!

Uodate:
And it seems to be already finished. The first batch for 20 units is closed.
Hope to see the next batch will be produced soon!

I thought it was just an announcement of the preorders starting this week?

By hamlet

Scribe (3721)

hamlet's picture

05-04-2021, 21:10

Thom wrote:

I thought it was just an announcement of the preorders starting this week?

This might be possible also. Maybe I misunderstood.

By hamlet

Scribe (3721)

hamlet's picture

06-04-2021, 10:41

8bits4ever will be opening preorders for the SX-2 first batch on Wednesday 7th April around 2 PM (GTM+2 time). You will be able to preorder directly from the product page. There is no reserves or waiting lists.

They will set up a page where you will be able to check the status of your unit, if its already in production, if shipped, etc.

By ssfony

Expert (83)

ssfony's picture

07-04-2021, 14:07

I just ordered one Big smile

By journey

Hero (537)

journey's picture

07-04-2021, 14:08

Same for me!! Smile

By bsittler

Master (246)

bsittler's picture

07-04-2021, 14:26

Congrats! I reloaded a few times but always got "out of stock", I hope there will be another batch soon. Also impressed the batch appears to have sold out in only a few minutes

By 8bits4ever

Resident (51)

8bits4ever's picture

07-04-2021, 15:24

It was sold out in about two minutes, literally. We will have more soon, dont worry.

Probably we will focus solely on the SX2 production for the coming weeks so we can have more units available sooner

By Angelo Sanna

Rookie (29)

Angelo Sanna's picture

08-04-2021, 01:01

rolandve wrote:

I've got some 8bit4ever products and I support their line of business.

I can confirm this, 8bits4ever delivers very good quality and knows the trade of electronics. Recommended hardware seller for MSX.

By msxtrd

Master (254)

msxtrd's picture

09-04-2021, 11:10

Someone snatched "mine", before I completed the payment Sad. Gone in 4 minutes, wohooo...

By Pencioner

Scribe (1478)

Pencioner's picture

09-04-2021, 12:34

msxtrd wrote:

Someone snatched "mine", before I completed the payment Sad. Gone in 4 minutes, wohooo...

Aww man, it hurts...

By mfeingol

Champion (291)

mfeingol's picture

09-04-2021, 19:22

I have a Zemmix NEO made in Brazil. Nice machine, but I'd upgrade it to this if it came with direct HDMI support. I have a VGA to HDMI converter but I don't particularly like the results and would definitely prefer direct digital output.

By bsittler

Master (246)

bsittler's picture

09-04-2021, 20:44

I know it's unrealistic but I hope the next batch can be in stock a bit longer before selling out, and ideally during the California daylight hours. In any case I'm looking forward to it and I hope to read more shared on this site in the future from those who got one from the first batch too!

By bsittler

Master (246)

bsittler's picture

11-05-2021, 00:02

Looks like a few more units became available! https://www.8bits4ever.net/product-page/sx2-msx-fpga

Thanks again for making new MSX hardware @8bits4ever :)

By hamlet

Scribe (3721)

hamlet's picture

11-05-2021, 07:07

My 4 slot SX-2.

By bsittler

Master (246)

bsittler's picture

11-05-2021, 18:15

@hamlet what is the expander in the back slot? Is that one commercially available somewhere?

By hamlet

Scribe (3721)

hamlet's picture

11-05-2021, 21:37

The expander board was sold by 8bits4ever origin for the SX-1. It also matches to the first SX mini edition that has come only with the extensions bus, without cartridge slots.

By 8bits4ever

Resident (51)

8bits4ever's picture

12-05-2021, 17:33

hamlet wrote:

The expander board was sold by 8bits4ever origin for the SX-1. It also matches to the first SX mini edition that has come only with the extensions bus, without cartridge slots.

Be aware the select line for the second slot on the module will be connected to ground. Only module's slot 1 will work, so you get effectively 3 slots in total (not 4)

By bsittler

Master (246)

bsittler's picture

15-06-2021, 06:22

Got one delivered today and love it so far! Having built-in Wi-Fi with automatic NTP synchronization is great for file timestamps Smile Also the option for lots of RAM (large memory mapper) is quite handy

When I tried it with the 8bits4ever slotx4 expander directly wired to the expansion port I was surprised that multiple slots work. Does anyone know the slot map for it?

Also does it support keyboard toggling of slots like SX-1 Mini+ or only boot time DIP switch toggling?

what is the mysterious OPL/which software supports it? Is it possible somehow to use Moonsound software despite it being OPL3 rather than OPL4?

The MIDI-PAC v2 worked in the slot expander but not in either main slot. Is 12 V power missing perhaps? Or did I use an insufficient power supply?

What is each audio jack? i naively expected the green one to be the output but it seems the black one is actually? Also the PS/2 ports aren't labeled. Is there some way to toggle between PS/2 mouse and DE-9 port for a controller?

Apologies if there is documentation for this all, I did look but am not sure which documentation applies

By funky327

Supporter (1)

funky327's picture

08-08-2021, 03:06

Quote:

Can the PS/2 ports source sufficient power for an active conversion adapter so that more modern USB peripherals can be used with this? In the SX-1 mini+ I use this one for the keyboard and connect a Logitech unifying receiver wireless keyboard dongle to it: https://www.amazon.com/Adder-KVM-konverter-USB-KMU2P/dp/B005... (I use it with this keyboard wirelessly: https://www.amazon.com/Logitech-Advanced-Wireless-Illuminate... )

@bsittler: In regards to the PS/2 ports, what were you able to find out as to whether a PS/2 to USB adapter can be used?

Thanks!