mist-devel/mist-board

Core sources and tools for the MIST board

For further information see our Wiki or jump directly to the Getting started page.

Get your own MIST board e.g. from Lotharek in Poland, AMedia in France, Amigastore in Spain or Retrolemon in UK

The MIST board was designed to implement classic 16 bit computers like the Amiga and Atari ST(E) as System-on-a-Chip using modern hardware. But it equally well supports 8 bit systems like the Atari XL, ZX81, ZX Spectrum, C64, Atari VCS, Atari 5200, Colecovision, Apple II, Sega Master System, NES, Odyssey2 and more ...

This repository contains the source code of many cores. Further cores can be found in various other repositories like:

• Winfried Soltys' github repository
• Sorgelig's github repository
• Rok Krajnc's github repository
• Robinsonb5's github repository
• Gehstock's github repository
• Gyurco's github repository

mist-board's Issues

This is not an issue but an idea for the firmware.

The uController has limited space and to program it you need extra hardware (if things go really wrong).

My idea is something like U-Boot (this could be reused and make it load the firmware it self from the SD Card) or to make or adapt the current firmware and divide it into several parts.

A generic one in the flash of the uController ( like a B.I.O.S. ) and another or others in the sd card, someting like modules, plugins (some of them could even be dedicated to a specific core).

Then each module/plugin could be made without storage reservations and it could be changed whitout reflashing the uController.

I know this is crazy at this point, meaning that the firmware would have to be reimplemented, but the possibilities of this could be huge.

One of them would be external drivers, for several USB devices.
Other things like supporting compressed roms transparently for the core.
Make several addons like a file manager, menu manager(Like RetroPie) and so on.

I'm thinking of the support for several usb devices that some users don't use and others use, so the uController wouldn't have to have all the software in the flash meaning the it could be used for something else like a tcp stack implementation that could be made available in a serial port or something like that. giving access internet access to several cores.(Spectranet, etc...)
Besides the future developemnts could be made as plugins and the support of the code would be more simple.

Now you guys can call me crazy, but this was just an idea. Despite of my lunatic ideas you guys are making an exelent work especialy Till.

Thank you for this wonderfull project.

Best regards.
Rui Magro.

MIST/Minimig DAC has stray noise

I left my sigma delta book at work and I cannot check whether stray is the right word. The effect is well known for sigma delta DACs: some input signals may cause the output to become unstable for a while, until it eventually fades away.

Here is an example of that situation with the MIST/Minimig DAC. In the image you can see the audio capture from the DAC at the top, and at the bottom the same audio captured digitally. You can see how the digital version is stable in the middle, while the other starts to stray away only to stop when the input signal changes totally.

You can also hear to the right sound here. And the DAC sound is here.

If you listen to the full song you can catch this issue more times, but it requires paying more attention to it. I leave the files in case someone is curious:

Full song
Correct sound
MIST DAC sound

ZX Spectrum core doesn't work

Hi!
Not sure where to get support for this, but none of ZX core binaries work with either latest firmware and 20150910. Since 20150910 is the minimum required for Amiga AGA core i cannot go to earlier versions.

Oldest available ZX core doesn't support RGBS mode, but it seams shows some start Spectrum dialog. I cannot use it because my scaler cannot sync doublescan frequency. From second to latest ZX cores hang on startup with garbage on screen.

Is it possible to get updated (may be simple re-compilation required?) ZX core binary?

Would this support Master System/Genesis joysticks?

They use the same joystick port as the Atari joysticks so I wonder if it would be possible to support them (at least if anyone ever writes a Genesis core).

BBC Micro SDHC Support

The BBC core claims to not support SDHC but I think this is wrong having read the documentation.

The mmb file always needs to be the first file added to the SD card so should always lie in the first 2GB and therefore meet the requirement for SDHC Support.

I will try and get round to more testing soon and report back. (As well as having a go at adding Midi to the core).

Thanks for this awesome project!

FordP

ZX Spectrum: OSD is not correct in TV RGBS mode.

With scandoubler_disable=1 in mist.ini, OSD is rolling vertically.

Purpose of R21? (affects the sound)

While debugging SAA1099 module and pulling my hair from everywhere while trying to fix stereo sound, I've discovered MiST having very noticeable audio channel cross-talking.
An then I've discovered resistor R21 on the board mixing LR together.
Why?
I'm not 100% sure if it will fix the problem when i remove this resistor, but i have no idea what is the purpose of this resistor.

15Khz support for NES core

15Khz support for the NES core would be wonderful because I could get a beautiful RGB output instead of the dull RF of the real hardware.

I can see that it is done using the scandoubler_disable parameter but I currently have absolutely no experience with fpga ( cough neither electronics cough ) so I don't have any idea about where to start.

Could you give some hints ?

bbc_mist_top.qpf

Hi I just tried to open the BBC project file and it says it has errors on my Quartus II 13.0.1.

Any ideas how to proceed. I want to prove I have I can build an exact copy of the project sof file before I start to make improvements.

Cheers.

FordP

[Feature req.] Keyboard Shortcuts

Issue by GoogleCodeExporter
Thursday Jul 30, 2015 at 20:44 GMT
Originally opened as https://github.com/mist-devel/_mist-board_OLD/issues/2

---

If its possible, please:
Keyboard shortcuts for

Reset 
Cold Reset
Change Monitor Mode (color /mono)
NMI (usefull for debug/code monitors/rippers)

Can the AltGR + any other key be mapped for this task?

Original issue reported on code.google.com by [email protected] on 25 Jul 2013 at 2:50

install_arm-none-eabi-gcc.sh is not complete

Building of gcc has failed because required libs are missing: MPC, MPFR, GMP
I believe some linux distro have these libraries installed and thus gcc will be built successfully, but for general case it's better to download these libs and put into gcc source folder - and they will be automatically picked by compiler.
That's how i've compiled it in Ubuntu 14.1.

I hope i won't need ARM JTAG soon ;)

NES Core: SuperMarioBros running too fast?

I compared the speed of gameplay with videos on youtube: is it just my impression or does the MiST NES Core run "too fast"?

Split the sources

@harbaum,
Could you consider to split the sources of cores into separate repositories?
It will be more easier to provide the support because developers can work on specific cores without forking into separate repo.
Also, it would give a chance to prune non-used sources. For example ZX and minimig cores are no longer used in this repository and may mislead new developers.
Wiki already provides links for repositories for each core, so it can be used as a central hub to gather all used repositories.

Amstrad Core Issues

The core does not support the the bundled CP/M+ software.

With a valid working CP/M+ Disc1 image mounted, the systems returns with the following message after issuing the |cpm command.

"This program will not run in this environment. Press any key"

Also there seems to be no way of adding a second floppy disk drive to the core.

about resolution in video.v

Hello everyone
first, I don't know if it's the right place to ask questions about the HDL code.

I have checked the video.v,
I think your idea it is put orignal 256_240 (mode = 1), 512_480 (mode=0,smoothing=0)and 512*480 with hq2x optimzation(mode=0,smoothing=1) into one module which is very good.
but it raises some questions to me,

<1>. take your code:
wire hpicture = (h < 512); //this does not make sense, why not hpicture = (h < (512>>mode));
wire hend = (h == 681); //again ,why not hend = (h == (681>>mode) )
wire vpicture = (v < (480 >> mode));
wire vend = (v == (523 >> mode));

assign VGA_VS = mode ? 1'b1 : ~sync_v;//when mode =1, VGA_VS is always high?

<2>. have you test nes on modelsim?
I have tried and failed ,because many signals are unkown (x state) during simuation cause cpu stop at some instruction.
and I do some modification by initialize signals in initial statement or during reset , but I can‘t fix it all because i am a newbie.

Commodore 64 core dont load TAPs images

Hello, I don't know if I should put this here...
it would be possible to implement in the core of commodore 64 load from TAP or T64 load images?

Thanks.

Mice on atari core

Is there any news about mouse support on the atari core like on the minimig core ?
I tried som rs232 to usb cable with no success and i would like use my old mouse with my mist :)

1GB HDD image is causing critical system error

From @GoogleCodeExporter on July 30, 2015 20:44

What steps will reproduce the problem?
1. Attach the HDD image from http://8bitchip.info/atari/DiskImgPP1.html

What is the expected output? What do you see instead?

System should be boot normally to Desktop.
There is a big row of bombs filling the middle of the screen.

What version of the product are you using? On what operating system?

MiST ST core r121.

TOS 1.04, KaosTOS, TOS 2.06, SuperTOS 2.06


Please provide any additional information below.

Original issue reported on code.google.com by [email protected] on 25 Jul 2013 at 9:11

Attachments:

• P1110496.JPG

_Copied from original issue: mist-devel/mist-board_OLD#1

TRS-80 core?

Was just looking to see if a TRS 80 core was available .. I see other Z80 based systems that are more complex that the TRS80..

"Panic: Bus Error." with new MIST and Atari ST emulation

Hi,

I've just received a new MIST from Lotharek and am trying to follow the instructions on https://github.com/mist-devel/mist-board/wiki/GettingStarted to get the Atari ST emulation running. When I start the box, I see this message:

Panic: Bus error.
misc = 2314, address = 00e02314, opcode = 2314, sr = 2314, pc = 00e06e82
Dregs: 0000ff00 000003e8 00000000 00000000  0000ffff 00000000 00000000 00000000
Aregs: 00000000 00000522 00004a4c 00000000  01000000 00000200 00e00b38 00000ede
 usp = 00000000

It seems that the m68k is running, but somehow crashes. I've tried both the files linked from GitHub as well as the files present in the Subversion repository. I've tried a few of the other bitstreams (colecovision, spectrum, Amstrad), and they all seem to work to some degree. Does anyone know whether this is a hardware or software issue?

Thanks!
Hans

Wrong scart cable schematic

The VGA plug in the scart cable schematic is mirrored - https://github.com/mist-devel/mist-board/wiki/ScartCable

C64: incorrect blanking

Since i've got hardware supporting scandoubler video, i've started to check cores in this mode.

C64 core in scandoubler mode is very very dark. Picture is barely noticeable.
After checking source code, i've found this:

    hSync <= hBlanking;
    vSync <= vBlanking;

So, basically Monitor (and TV) has no blanking signals to adjust color gains and treat the border as a black level. Actually, it's true even for TV mode, but somehow other converter pick correct black level and picture is correct in PAL mode.
I think, the picture depends on specific monitor/TV where some displays will show correct picture, while other may show very dark picture.

In general, core should be fixed to have blank level samples. The C64 core is quite complex and i'm not sure if i will be able to fix the problem. Can try to reduce hSync/vSync if there is a room.

BBC Micro core no OSD with 15khz RGB

The OSD works fine in VGA but with 15khz RGB it does not appear.

CoreDocAtari800 - Dead links

Links to the Atari 800 docs and cores are dead.

Website appears to have been changed to: http://www.64kib.com/

Possibilty of ethernet on Amiga core?

Is it at all doable?

1GB HDD image is causing critical system error

Issue by GoogleCodeExporter
Thursday Jul 30, 2015 at 20:44 GMT
Originally opened as https://github.com/mist-devel/_mist-board_OLD/issues/1

---

What steps will reproduce the problem?
1. Attach the HDD image from http://8bitchip.info/atari/DiskImgPP1.html

What is the expected output? What do you see instead?

System should be boot normally to Desktop.
There is a big row of bombs filling the middle of the screen.

What version of the product are you using? On what operating system?

MiST ST core r121.

TOS 1.04, KaosTOS, TOS 2.06, SuperTOS 2.06


Please provide any additional information below.

Original issue reported on code.google.com by [email protected] on 25 Jul 2013 at 9:11

Attachments:

• P1110496.JPG

BOM and Gerber files

Hi,
Did you agree to release the BOM and Gerber files for Mist ?
I'm interrreted in your project but ressellers sells it with an heavy price ...
Really it's too much for thats parts.

With a complete hardware release , it will be possible to build and home made Mist.

Regards.

Nice smoke test for the C= 64 core

This demo seems to work only on real hardware and in micro64. VICE, Emu64 and MiST fail.

http://csdb.dk/release/?id=146723

SPI speed

This is a documentation request:

I am writting a core and using the SPI modules to communicate with the microcontroller, as expected. I do not know what frequency the microcontroller is using to send the data, so I cannot constraint the clock in my core for synthesis. The frequency of SPI_SCK is what I need.

Could someone tell me? And, could someone update the Wiki on this page so this information is available?

Apart from the SPI clock speed, do we need to set up any other constraint type to deal with latencies through the pins or the SPI clock edge is already on the stable side of the data waveform?

Thank you

Archimedes RISCOS in German

For some reason, on the Acorn Archimedes core, every riscos rom I try is in German. I'm sure it's not the roms, as there's no mention of them being a German version.

SMS core: won't play VGM songs embeded in .sms file

I've tried to load sms files using the vgmplayer used by the DefleMask music tracker (it embed vmg file into a SMS rom).
On an emulator such as Kega-Fusion, it loads and plays well. With the latest SMS core, I get a screen saying: "No VGM file has been found by the player. etc."

A sample file to test this error: https://mega.nz/#!8sZETDzb!5Pdfqo88_s-MvuaG0_KpC8X_-YCVaoMY40g3_Jyv7UE

[NES core], support for swapping buttons needed

Thanks for all the work you are doing!

Would like to see a possibility for the NES core to swap A/B buttons at least, or assign them. I have couple of NES -controller -> USB adapters, and by default with these, the A and B buttons are swapped from the original.

Can you implement this or is the source code maybe available somewher so I can take a look?
Thanks!

[Feature req.] Keyboard Shortcuts

Issue by GoogleCodeExporter
Thursday Jul 30, 2015 at 20:44 GMT
Originally opened as https://github.com/mist-devel/_mist-board_OLD/issues/2

---

If its possible, please:
Keyboard shortcuts for

Reset 
Cold Reset
Change Monitor Mode (color /mono)
NMI (usefull for debug/code monitors/rippers)

Can the AltGR + any other key be mapped for this task?

Original issue reported on code.google.com by [email protected] on 25 Jul 2013 at 2:50

multicomp really ported to mist?

In the fpga projects section of this wiki it reads:

Multicomp Link yes Has been ported to the MIST

Has this really been ported to MiST, already? If so, where can I find this port? I built the multicomp Z80 CP/M system using the same Chinese Cyclone2 board and was considering to give it a try to port it to MiST, myself. But only if it does not exist, already.

Rene

Tools / ESCParser

I'm using ESCParser tool:
https://github.com/mist-devel/mist-board/tree/master/tools/ESCParser

It could be very useful, because it's compatible with "EpsonQ" driver from AmigaOS. But, I tried to convert a graphic output and I got this:

It seems like it have done more passes but interleaved.

b.ps.zip

Noise while loading from SD-Card

I'm having strange Sound issues when the SD-Card is being accessed. Seems to be some kind of crosstalk?

Plus_Too core: which .DSK and .IMG format?

Hi, I downloaded System6 .DSK files from here:
https://sites.google.com/site/minivmacapplicationsv6/systems-os
(specifically: https://sites.google.com/site/minivmacapplicationsv6/systems-os/System608.zip?attredirects=0&d=1)

...and a hard disk images from here:
http://digiex.net/downloads/download-center-2-0/applications/8541-mac-os-6-games-apps-emulator.html

None of them seems to work with plus_too core. What is the correct disk format? Is it possibile to convert them in a plus_too core compatible format?

1GB HDD image is causing critical system error

Issue by GoogleCodeExporter
Thursday Jul 30, 2015 at 20:44 GMT
Originally opened as https://github.com/mist-devel/_mist-board_OLD/issues/1

---

What steps will reproduce the problem?
1. Attach the HDD image from http://8bitchip.info/atari/DiskImgPP1.html

What is the expected output? What do you see instead?

System should be boot normally to Desktop.
There is a big row of bombs filling the middle of the screen.

What version of the product are you using? On what operating system?

MiST ST core r121.

TOS 1.04, KaosTOS, TOS 2.06, SuperTOS 2.06


Please provide any additional information below.

Original issue reported on code.google.com by [email protected] on 25 Jul 2013 at 9:11

Attachments:

• P1110496.JPG

MiST Color Mode Constrained

On the MiST core set to color mode the screen is scaled far too large for some LCD monitors. Maybe there's a way to multiply the VGA video output resolution? All others scale properly except MiST color mode. Tried the video settings in menu and they do not change it. says it's 640x350 when it's 640x200 or 320x200. LCD supports 640x400 fine, but apparently also 640x350 is the lowest setting so being unable to force the video scaler maybe a 350 output option so the display will just shrink to normal resolution at 200 and have black bars? Or force 400 so the vertical is constant. Probably better monitor compatibility that way.

Archimedes floppy files

In the instructions for setting up for Acorn Archimedes you state the following:

"Floppy disk images ADF format and of exactly 819200 bytes in size are currently required."

How do I make those? I have WinUAE and it will only create specific fixed sizes, none of which are 819200 bytes!
The closest is "Create Standard Disk" with "3.5" DD (PC)" selected which creates a disk file of 737280 bytes (720KB).
The next closest is "Create Standard Disk" with "3.5" DD (PC)" selected, creates a disk file of 901120 bytes (880KB).
After that all the other options are too big apart from one that is smaller than the 3.5" DD (PC) one.

Configure mouse sensitivity in mist.ini or any other way

Is there a possibility to configure mouse sensitivity in any way? When i run minimig the sensitivity is to high so it's almost impossible to use.

Graphical issues in C64 core

Please see Glider Rider for an example. The player sprite appears under the playfield. This may be due to iffy game coding (ie. Lame Spectrum port), but it still should work :)

[Feature req.] Keyboard Shortcuts

From @GoogleCodeExporter on July 30, 2015 20:44

If its possible, please:
Keyboard shortcuts for

Reset 
Cold Reset
Change Monitor Mode (color /mono)
NMI (usefull for debug/code monitors/rippers)

Can the AltGR + any other key be mapped for this task?

Original issue reported on code.google.com by [email protected] on 25 Jul 2013 at 2:50

_Copied from original issue: mist-devel/mist-board_OLD#2

C64 SID problems.

The SID code in C64 core doesn't look accurate. Sound in some tunes looks strange or messed in some cases.
For example, Intro with dancing girl (again dancing girl, haha!) in Hollywood Poker Pro is very messed.
And even tunes primarily considered OK, sound strange. Turrican II Title sound is too jerky...

One problem in SID code is noise generator. The second is total filter absence in code.

I've found another, unfortunately unfinished, SID FPGA project in fpgaarcade forum. That project is based on chip decaping according to author. I've made it work with C64 core, it also has issues, but what is working, looks correct. It seems like one channel is not working, and i didn't find the source of problem. But noise does look correct. It also has filters implementation, but according to author the filter part hasn't finished yet. I've imported noise generator to existing SID code from fpgaarcade project. Noise is better, but not enough to be acceptable.

Does anyone now other FPGA SID implementations? Or may be someone can help to fix the problems by mixing these 2 SID implementations?

MIST core: Timing constraints not met

The MIST core has timing issues and does not get synthesized correctly. Some implementations do seem to work nicely but others fail from the very beginning.

Constraints and operating conditions need some redifinition and the design probably needs some refinement too in order to avoid these timing problems.

---

TimeQuest Timing Analyzer Summary

Type : Slow 1200mV 85C Model Setup 'clock|altpll_component|auto_generated|pll1|clk[1]'
Slack : -9.438
TNS : -1947.729

Type : Slow 1200mV 85C Model Setup 'clock|altpll_component|auto_generated|pll1|clk[0]'
Slack : -5.792
TNS : -380.770

Type : Slow 1200mV 85C Model Setup 'sdclk_pin'
Slack : -4.515
TNS : -70.551

Type : Slow 1200mV 85C Model Hold 'clock|altpll_component|auto_generated|pll1|clk[1]'
Slack : -3.855
TNS : -246.855

Type : Slow 1200mV 85C Model Hold 'sdclk_pin'
Slack : -1.071
TNS : -1.071

Type : Slow 1200mV 85C Model Hold 'clock|altpll_component|auto_generated|pll1|clk[0]'
Slack : 0.454
TNS : 0.000

Type : Slow 1200mV 85C Model Recovery 'clock|altpll_component|auto_generated|pll1|clk[1]'
Slack : 11.782
TNS : 0.000

Type : Slow 1200mV 85C Model Removal 'clock|altpll_component|auto_generated|pll1|clk[1]'
Slack : 18.677
TNS : 0.000

Type : Slow 1200mV 85C Model Minimum Pulse Width 'clock|altpll_component|auto_generated|pll1|clk[2]'
Slack : -3.952
TNS : -3.952

Type : Slow 1200mV 85C Model Minimum Pulse Width 'sdclk_pin'
Slack : -3.952
TNS : -3.952

Type : Slow 1200mV 85C Model Minimum Pulse Width 'clock|altpll_component|auto_generated|pll1|clk[0]'
Slack : 3.498
TNS : 0.000

Type : Slow 1200mV 85C Model Minimum Pulse Width 'clock|altpll_component|auto_generated|pll1|clk[1]'
Slack : 15.084
TNS : 0.000

Type : Slow 1200mV 85C Model Minimum Pulse Width 'clk_27'
Slack : 18.384
TNS : 0.000

Type : Slow 1200mV 0C Model Setup 'clock|altpll_component|auto_generated|pll1|clk[1]'
Slack : -8.486
TNS : -1542.736

Type : Slow 1200mV 0C Model Setup 'clock|altpll_component|auto_generated|pll1|clk[0]'
Slack : -4.993
TNS : -269.462

Type : Slow 1200mV 0C Model Setup 'sdclk_pin'
Slack : -3.484
TNS : -54.185

Type : Slow 1200mV 0C Model Hold 'clock|altpll_component|auto_generated|pll1|clk[1]'
Slack : -3.620
TNS : -234.595

Type : Slow 1200mV 0C Model Hold 'sdclk_pin'
Slack : -1.053
TNS : -1.053

Type : Slow 1200mV 0C Model Hold 'clock|altpll_component|auto_generated|pll1|clk[0]'
Slack : 0.402
TNS : 0.000

Type : Slow 1200mV 0C Model Recovery 'clock|altpll_component|auto_generated|pll1|clk[1]'
Slack : 12.003
TNS : 0.000

Type : Slow 1200mV 0C Model Removal 'clock|altpll_component|auto_generated|pll1|clk[1]'
Slack : 18.360
TNS : 0.000

Type : Slow 1200mV 0C Model Minimum Pulse Width 'clock|altpll_component|auto_generated|pll1|clk[2]'
Slack : -3.952
TNS : -3.952

Type : Slow 1200mV 0C Model Minimum Pulse Width 'sdclk_pin'
Slack : -3.952
TNS : -3.952

Type : Slow 1200mV 0C Model Minimum Pulse Width 'clock|altpll_component|auto_generated|pll1|clk[0]'
Slack : 3.361
TNS : 0.000

Type : Slow 1200mV 0C Model Minimum Pulse Width 'clock|altpll_component|auto_generated|pll1|clk[1]'
Slack : 14.984
TNS : 0.000

Type : Slow 1200mV 0C Model Minimum Pulse Width 'clk_27'
Slack : 18.369
TNS : 0.000

Type : Fast 1200mV 0C Model Setup 'clock|altpll_component|auto_generated|pll1|clk[1]'
Slack : -0.666
TNS : -1.178

Type : Fast 1200mV 0C Model Setup 'sdclk_pin'
Slack : -0.618
TNS : -9.021

Type : Fast 1200mV 0C Model Setup 'clock|altpll_component|auto_generated|pll1|clk[0]'
Slack : -0.491
TNS : -0.828

Type : Fast 1200mV 0C Model Hold 'clock|altpll_component|auto_generated|pll1|clk[1]'
Slack : -1.697
TNS : -112.795

Type : Fast 1200mV 0C Model Hold 'sdclk_pin'
Slack : -0.987
TNS : -0.987

Type : Fast 1200mV 0C Model Hold 'clock|altpll_component|auto_generated|pll1|clk[0]'
Slack : 0.185
TNS : 0.000

Type : Fast 1200mV 0C Model Recovery 'clock|altpll_component|auto_generated|pll1|clk[1]'
Slack : 13.793
TNS : 0.000

Type : Fast 1200mV 0C Model Removal 'clock|altpll_component|auto_generated|pll1|clk[1]'
Slack : 16.989
TNS : 0.000

Type : Fast 1200mV 0C Model Minimum Pulse Width 'clock|altpll_component|auto_generated|pll1|clk[2]'
Slack : -0.031
TNS : -0.031

Type : Fast 1200mV 0C Model Minimum Pulse Width 'sdclk_pin'
Slack : -0.031
TNS : -0.031

Type : Fast 1200mV 0C Model Minimum Pulse Width 'clock|altpll_component|auto_generated|pll1|clk[0]'
Slack : 3.554
TNS : 0.000

Type : Fast 1200mV 0C Model Minimum Pulse Width 'clock|altpll_component|auto_generated|pll1|clk[1]'
Slack : 15.283
TNS : 0.000

Type : Fast 1200mV 0C Model Minimum Pulse Width 'clk_27'
Slack : 17.946
TNS : 0.000

---

[C64] implement 2Mhz CPU speed for C128 running in C64 mode

there are some games (notably the new "Super Mario Bros") that are able to take advantage of the 2Mhz CPU speed that you can get when running the C128 in C64 mode.

I think it would be nice if we have this option in the MiST core too (e.g. "Enable 2Mhz 8502: Off;On;")

I tried to code it myself but got lost in the fine details of the state machine, sysCycleDef and the intricate jungle of enable signals. I thought it would be as easy as adding an extra CPU cycle, but of course it wasn't.

Summary of the 2Mhz mode:

• when enabled the C64 responds to the register $D030, otherwise the register is always $FF
• bit 0: when 1 => 2Mhz speed is active (not exactly 2Mhz, it's just that clock speed is doubled)
• bit 1: test bit (not used but can be read and written)
• other bits are always 1

When running at 2Mhz, the VIC-II can't cope with the new speed and displays garbage in the active area, but borders are ok. Games usually enable it during the blanking/border periods.

All other chips receive an effective 1Mhz frequency:

[...] the system employs an elaborate technique known as clock stretching, where the
clock period is extended to create an effective 1-MHz rate for the portion of the clock cycle when the I/O chip is being accessed.

C64 source code is missing.

Hi,

Patches in C64 core require vhdl_c64_c1541_sd.zip which is replaced by newer version and thus cannot be applied.
Can anyone upload vhdl_c64_c1541_sd.zip or already patched sfor MIST source code?

NES core missing sounds in Super Mario Bros 3

Hi,

Has anybody else noticed that the NES core is missing some SMB3 sound effects?
-The sound effect of Mario materializing on the map screen is missing.
-The sound effect of Mario flying with the tanooki or racoon suits has missing notes.

Only ST core works!

I just got my MiST 1.3 yesterday but so far I am only able to get it to work with the ST core. I have tried multiple versions of the Amiga core, the Spectrum core and the BBC core, they will not work.

If I boot with the ST core and try switching to the Amiga by selecting the Amiga core file on the SD card with a valid kickstart 3.1 ROM stored as kick.rom (I own Amiga Forever Plus and have licensed ROM files. No, I am not using the Amiga Forever ROM as it is encrypted with a key file, I have actual ROM files downloaded elsewhere). When I switch core using the OSD menu Firmware & Core sub menu the red LED flashes while it reads the core file then the amber LED comes on for 2 seconds then flashes 5 times before repeating that sequence of 2 seconds on then flash 5 times. The only information I can find on this site is that the red LED should be flashing for errors and 5 flashes means the core was not read properly.

I get the same result if I switch to the Spectrum core or the BBC core in the same way. Again the same result if I also switch the main ST core.rbf file with the Amiga one (rename them so the Amiga one is core.rbf and the ST one is another name). Again the same result. All cores I have tried (that I have system ROMS for) have the same result except for the ST core!

I did update the firmware to ATH170412.

I would like this to work. I spent a lot of money on getting this on the premise that it can be used to 'emulate' (yes I know it's not actual emulation) multiple machines. In particular ST AND Amiga. If I just wanted an ST I would have spent less getting a real ST :P

Support for Commodore / Atari Mouse, Dual Mouse-Support

What is needed to enable native Mouse-Support? I'd like to play Settlers in Splitscreen. Afaik USB-HIDs will not allow the use of two Mice simultaneously...