Forked from: javiwwweb/MisTerRFID Most of the ReadMe below is copy/paste from javiwwweb. I have added some notes for my changes.

Below are the currently supported cores:

Core
Amiga
Atari 5200,7800,800,Lynx
C64
GameBoy
GBA
Genesis
MegaCD
NeoGeo
NES
S32X
SMS
SNES
TGFX16/CD
PSX

Please report any bugs as an issue if you run into any.

Quick Start Guide
Hardware Needed
Arduino Hardware Setup
Write Card Setup
MiSTer Setup
- Manually Adding Cores
Use
- Assigning Games to Cards
Known Issues
Troubleshooting

MiSTerRFID

Enables RFID card launching of games for MiSTer FPGA. Launches games without any menu being displayed using the MiSTer Game Launcher files (MGL) method. Must use a version of MiSTer from Feb 24, 2022 or after to support this method of launching.

External ROM sources are supported (USB tested working. Network-based solutions should work, but untested).

This version allows you to assign games to cards without needing to edit the rfid_process.sh or game_list.conf file.

Hardware Needed

Arduino Nano V3.0
RC522 RFID Card Reader Module Board (3.3V)
Mi-fare door access cards
MiSTer FPGA with the extra USB ports board.

Arduino Hardware Setup

RC522 Module Pin	Arduino Pin
RST	D9
SDA	D10
MOSI	D11
MISO	D12
SCK	D13
VCC	3.3V
GRD	GRD

Arduino Software Setup

Download Arduino software
Connect Arduino Nano
Open arduino/misterrfid.ino
Go to Tools -> Manage Libraries and search for MFRC522
Install Easy MFRC522
Verify Installation and Upload

On your computer, attach the serial monitor to your Arduino and you should see it repeating . rfid_process.sh noscan about every second. As soon as your scan a RFID card, it should output . rfid_process.sh 12345678. The number is that card's unique ID. The reader will not scan the same card two times in a row. Make note of the card's unique id.

⚠️ Skipping steps below will cause your code to not function! ⚠️

If you find out that that you would like to extend the distance the card is picked up, You can adjust the receiver gain by editing line 22 of the arduino/misterrfid.ino and upload the code.

    rfid.PCD_SetRegisterBitMask(rfid.RFCfgReg, (0x03<<4)); // RFID Gain

The HEX 0x03 control the gain. In my case that was the value that would penetrate the wooden bezel and the glass at the perfect distance. You may need to adjust this value set the receiver's gain to your desired level

Gain Values in HEX
0x01 = 23 dB HEX
0x02 = 18 dB HEX
0x03 = 23 dB HEX
0x04 = 33 dB HEX
0x05 = 38 dB HEX
0x06 = 43 dB HEX
0x07 = 48 dB HEX

Write Card Setup

As you are gathering numbers from your cards or RFID tags, choose an RFID device that you'd like to use as a write card This card acts as a trigger to put your Arduino code into a loop that will run the rfid_write.sh file. The number of this RFID device needs to be replaced: 12346789 in arduino/misterrfid.ino at line 4. After you have done this, overwrite your Arduino with the new code. Set that card aside for later.

#define WRITE_TAG 1234567890

MiSTer Setup

Copy rfid_updater.sh from the Releases page to /media/fat/Scripts. Boot your mister, and run rfid_updater.sh from the Scripts folder. Continue to Use when this is done.

Note: If you use TTY2OLED, make sure you assign the right ttydev to the right device.

Manually Adding Cores (Optional)

Although the preferred method for adding games is by using the write card, you can manually add games to game_list.conf for unsupported files or if you find it easier/quicker.

Gather card numbers using the arduino serial monitor
If the game is an arcade core (.mra extension):
- use the absolute path for the .mra file. Please see the example below.
If the game is not an arcade core:
- create an mgl file for the game
- You can create these almost anywhere, but I recommend creating them the same place that rfid_write.sh would, which could be: /media/fat/games/CORE/GameFolder/Game.mgl An example MGL is shown below. Note: the GameFolder doesn't exist for all cores and is dependent on your directory hierarchy.
Starting on line 4 of game_list.conf add games using the following format. Please be advised that the space between CARDNUMBER and echo is a TAB, not spaces.

Manual Console Core Example

CARDNUMBER	echo load_core "/absolute/path/to/rom/file.mgl" > /dev/MiSTer_cmd
1452135431	echo load_core "/media/fat/games/PSX/Crash Bandicoot/Crash Bandicoot.mgl" > /dev/MiSTer_cmd

Manual Arcade Core Example

CARDNUMBER	echo load_core "/absolute/path/to/arcade/rom.mra" > /dev/MiSTer_cmd
5132153135	echo load_core "/media/fat/_Arcade/1942.mra" > /dev/MiSTer_cmd

MGL Example

The filename of this example would be: Crash Bandicoot.cue

The absolute filepath of this example would be: /media/fat/games/PSX/Crash Bandicoot/Crash Bandicoot.cue

Relative to the games folder for the PSX core is: Crash Bandicoot/Crash Bandicoot.cue

<mistergamedescription>
<rbf>_Console/PSX</rbf>
<file delay="2" type="f" index="0" path="Crash Bandicoot/Crash Bandicoot.cue"/>
</mistergamedescription>

Use

After running rfid_updater.sh, making any changes, or uploading files to your MiSTer, power it down.
Plug your Arduino into an available USB port on your USB board module and turn on your MiSTer. Depending on how many scripts you have running, it can take up to 30 seconds from first turning on the power to the RFID reader becoming available.
Once the RFID is available, you can start lunching games (if you added games to the game_list.conf file), or begin Assigning Games to Cards

Note: This can be combined with MisTer.ini option bootcore= to automatically launch an arcade core (MRA file) upon starting up your MisTer. The rfid_process.sh will run in the background waiting for a card to be presented.

Assigning Games to Cards

Launch a game using the core menu. Once the game has booted, scan your write card. This will tell the Arduino that it needs to run the rfid_write.sh file on the next card scan.
Scan a new (or already assigned) card. The card will be programmatically added to game_list.conf and the next time you scan that card, it will boot the game.
Remember that you cannot scan the same card twice, though. Scan a different card before scanning the just-written one in order to test it.

Cards can be overwritten. If you attempt to scan a card that is already added to the game_list.conf file, the entry will be deleted and then reassigned to the new game. You can do this as often as you'd like.

Games cannot be assigned/added when booted from an MGL file. You must do this process after booting from the Menu Core!

Known Issues

NeoGeo games must use the .neo extension. You cannot use a darksoft roll-up without converting to .neo. This is a limitation from .mgl files and how they load.

Troubleshooting

Check that your MiSTer.ini file(s) has log_file_entry=1
If your cards don't seem to be scanning in MiSTer, make sure that serial_listen.sh actually started. I have had issues with that not booting in the past. Re-imaging my SD card takes care of this if nothing else.
If games aren't being added to the right spot, or being injected in odd places in game_list.conf make sure you respected the format into game_list.conf. Read MiSTer Setup.
If your write card doesn't function, make sure you added the card number to the Arduino code and re-uploaded after making that change.

Quick Start

Set up your Arduino and MFRC522 using: Arduino Hardware Setup
Write the code to the Arduino
Pick a card to be the write card, scan it with the serial listener open, and jot down the number
Replace the value for WRITE_TAG in arduino/misterrfid.ino with your card number
Re-write to the arduino
Add rfid_updater.sh from the Releases page to Scripts folder and run it.
Follow the Use section

THANK YOU

Thanks to illusion-pasture-program and javiwwweb for the initial code and ideas. Thanks to @mrchrisster for their clarifications in the ReadMe and @coded-with-claws for their code and testing contributions!

ElRojo/MiSTerRFID

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