JTGNG FPGA Arcade Hardware by Jose Tejada (@topapate)

You can show your appreciation through

Yes, you always wanted to have a Ghosts'n Goblins arcade board at home. First you couldn't get it because your parents somehow did not understand you. Then you grow up and your wife doesn't understand you either. Don't worry, MiST(er) is here to the rescue.

What you get with this is an extremely accurate (allegedly 100% accurate) clone of the original hardware. You will notice differences from MAME if you compare. For instance, on Ghosts'n Goblins try resetting it and compare those screens for a start! Original hardware handled sound and graphics in a different way from the emulator. There were delays in CPU bus access and other details that will make the experience different from an emulator.

I hope you will have as much fun with it as I had it while making it!

Supported Games

In chronological order:

Dependencies

Game	6809	Z80	68000	MCU	YM2203	YM2151	YM2149	MSM5205	SN76489AN
1942		X					X
1943		X			X		X
Bionic Commando		X	X	X		X
Black Tiger		X		X	X		X
Commando		X			X		X
Exed Exes		X					X		X
F1-Dream		X	X	X	X		X
Ghosts'n Goblins	X	X			X		X
Gun Smoke		X			X		X
Higemaru		X					X
Legendary Wings		X			X		X
Section Z		X			X		X
Side Arms		X			X		X
Street Fighter		X	X	X		X		X
The Speed Rumbler	X	X			X		X
Tiger Road		X	X		X		X	X
Trojan		X			X			X
Vulgus		X					X

Games using 1943 scroll module

1943 / Gun Smoke
Trojan
Tiger Road / F1 Dream
Side Arms

Games re-writting the sprites to SDRAM

The Speed Rumbler
Tiger Road / F1 Dream
Bionic Commando

Games using multiple SDRAM banks

Bionic Commando
Street Fighter
The Speed Rumbler

Some modules identify the location of graphic bits, such as horizontal flip, with the help of a LAYOUT parameter. Here are the values:

Layout	Game
10	The Speed Rumbler
11	Exed Exes
12	Exed Exes (SCR2)

Wait States

Bus contention is similar across the different boards.

Game	Char Access Ok	Scr Access Ok
GnG	H[2:1]!=3	H[2:0]<2
1942	H[2:1]!=2	H[2:0]<3
1943, Side Arms	After H[2:0]==4	No SCR RAM
Commando	After H[2:0]==4	Wait until H[0]==0

YM2203 Clock Divider

These are the settings for the internal clock divider in YM2203 games. Each number refers to a YM22003 chip. This information can be viewed on the debug_view bus when compiled with JTFRAME_DEBUG.

Game	Divider	FM IRQ
1943	0/0	No
Black Tiger	2/2	Yes
Commando	0/0	No
F1-Dream	2/2	Yes
Ghosts'n Goblins	3/3	No
Gun Smoke	3/3	No
Legendary Wings	3/3	No
Section Z	3/3	No
Side Arms	2/2	Yes
The Speed Rumbler	2/2	Yes
Tiger Road	2/2	Yes
Trojan	3/3	No

Note that 2 is the default divider, so games using it may never set it explicitly.

Troubleshooting

If you have in-game problems, please read the text file specific to that core. Sometimes it's just that the games has more buttons than you think.
F1-Dream and Black Tiger are using an IP for the MCU that does not synthesize correctly at 48MHz because of a setup timing violation. Using the clock enable signal to operate it seems to remove the problem. Ideally, the IP should be edited to increase its frequency performance.
How to continue the game: many CAPCOM games of this era require to hold the fire button while pressing 1P to continue the game.

Keyboard

On MiSTer keyboard control is configured through the OSD.

For MiST and MiSTer: games can be controlled with both game pads and keyboard. The keyboard follows the same layout as MAME's default.

F3      Game reset
P       Pause (in some games, you can disable the credits screen by pressing 1P)
1,2     1P, 2P start buttons
5,6     Left and right coin inputs

cursors 1P direction
CTRL    1P button 1
ALT     1P button 2
space   1P button 3

R,F,G,D 2P direction
Q,S,A   2P buttons 3,2 and 1

F7      Turn character layer on/off
F8      Turn second background layer on/off
F9      Turn first  background layer on/off
F10     Turn object (sprite) layer on/off

ROM Generation

Each core in the releases folder continues files for linux and windows to generate the ROM file starting from a MAME set. Follow the instructions of that file. There are also MRA files available in the JTBIN. MRA files are the recommended way. Use the MRA-to-ROM converter from Sebdel if your device does not accept MRA files natively.

SD Card

For MiST copy the file core.rbf to the SD card at the root directory. Copy also the rom you have generated with the name JTGNG.rom. It will get loaded at start. Make sure to have a recent version of MiST/SiDi firmware.

Extras

You can press F12 to bring the OSD menu up. You can turn off music, or sound effects with it. By default, a screen filter makes the screen look closer to an old tube monitor. If you turn it off you will get sharp pixels. Note that if you switch from sharp to soft pixels you will need a couple of seconds to get your eyes used as the brain initially perceives this as an out of focus image compared to the old one.

Misc

Original filter for sound (GnG) -high pass filter with cut-off freq. at 1.6Hz -low pass filter with cut-off freq. at 32.3kHz

Modules

The FPGA clone uses the following modules:

JT12: For YM2203 sound synthesis. From the same author. JT51: For YM2151 sound synthesis. From the same author. JT5205: For MSM5205 ADPCM sound. From the same author. JTFRAME: A common framework for MiST arcades. From the same author. MC6809 from Greg Miller T80: originally from Daniel Wallner, with edits from Alexey Melnikov (Mister) hybrid_pwm_sd.v copied from FPGAgen source code. Unknown author

Use git clone --recurse-submodules in order to get all submodules when you clone the repository.

Compilation

Refer to JTFRAME for compilation instructions.

Directory Structure

model/gng/hdl/ replica of original PCB schematics model/gng/ver/ simulation files for original PCB modules files shared by several games and external files modules/mist doc documents related to original PCB doc/74 74' series data sheets rom script to convert from MAME rom files to the required format simulation files expect the rom files here cores/gng/ MiST board version of Ghosts'n Goblins. Latest core version is located in this folder and called core.rbf cores/gng/hdl Verilog files of the clone for MiST cores/gng/doc documents related to MiST clone or MiST hardware cores/gng/quartus project to synthesize the clone cores/gng/ver simulation files of MiST clone

cores/1942 MiST board version of 1942 arcade game cores/1942/hdl Verilog files of the clone for MiST cores/1942/zxuno files for ZX-UNO version cores/1942/mist Quartus files for MiST version

cores/1943 MiST board version of 1943 arcade game cores/1943/hdl Verilog files of the clone for MiST cores/1943/mist Quartus files for MiST version etc.

HDL Code Structure

The top level module is called jtgng_mist. This is the module that is really dependent on the board. If you want to port jtgng to a different FPGA board you will need to modify this file. Most other files will likely stay the same

The game itself in module jtgng_game. It is written using an arbitrary clock (active on positive edge) and a clock enable signal (switching on the negative edge). From jtgng_game down the hierarchy, everything should be highly portable.

The video output is a 256x256 screen. That is what you get from jtgng_game in a signal format that replicates the original hardware. jtgng_mist instantiates a module called jtgng_vga that converts the image to a standard VGA resolution without losing frame speed.

Credits

Jose Tejada Gomez. Twitter @topapate The project is hosted in http://www.github.com/jotego/jt_gng License: GPL3, you are obligued to publish your code if you use mine

Special thanks to Greg Miller, Bruno Silva and Alexey Melnikov

Thank you all!

+--------------------------------------------------------------------------------+
|oooooooooooooooooooooooooooooooooo+++++++++++ooooooooooooooooooooooooooooooooooo|
|ooooooooooooooooooooooooooooooooo+. .    . .+ooooooooooooooooooooooooooooooooooo|
|ooooooooooooooooooooooooooooooooo~         :o++ooooooooooooooooooooooooooooooooo|
|oooooooooooooooooooooooooooo+ooo+.        .++.:oo+oo+oooooo+o+oo+oooooo++ooooooo|
|ooooooooooooooooooooooooo+.......          .. .............................:oooo|
|oooooooooooooooooooooooo+.                                                .+o+oo|
|oooooooooooooooooooooooo:                                                 :o:.+o|
|ooooooooooooooooooooooo+.                                                .++.:oo|
|ooooooooooooooooooooooo:.....           ...........          ....... ....:o~.+oo|
|oooooooooooooooooooooooo+++++~         ~+++:++:++++.         ++++++++++++++.+ooo|
|oooooooooooooooooooooooooo+:~         .++.~:::::::.         .o+.~:::::::::::+ooo|
|oooooooooooooooooooooooooooo:         :o~.+oooooo+.         ++.~oooooooooooooooo|
|ooo~........~oooooooooooooo+.        .++.:ooooooo+         ~o:.+oooooooooooooooo|
|oo:         ~o++ooooooooooo.         +o~.ooooooo+.        .++.~ooooooooooooooooo|
|oo.         :+.:ooooooooo+.         ~o+.+ooooooo:         ~o:.+ooooooooooooooooo|
|oo.         ...~:::::::..          .++.~ooooooo+.        .o+.:oooooooooooooooooo|
|oo~                               ~o+..+ooooooo~         +o~.+oooooooooooooooooo|
|oo+.                           .~+o+..+ooooooo+.        .o+.+ooooooooooooooooooo|
|oooo~.                       .:+o+..:+oooooooo.         +o..oooooooooooooooooooo|
|ooooo+:...              ..~:+++:..:+ooooooooo+         .o+.+oooooooooooooooooooo|
|ooooooo+++::::::::::++++++++~~.~++ooooooooooo+:+:::::+:++.~ooooooooooooooooooooo|
|ooooooooo+++:::::::::~:~~~~:++oooooooooooooooooo+::::~::~.+ooooooooooooooooooooo|
|oooooooooooooo+o+oo++++o+ooooooooooooooooooooooo+o+++o++o+oooooooooooooooooooooo|
+--------------------------------------------------------------------------------+