Playchoice-10 custom instructions


Custom INST-ROM is made using a homebrew game called Magic Floor ( ).

You need the following:
  •     Magic Floor assembler source code (
  •     NO$NES emulator ($ )
  •     PC-10 dual monitor bios

Rename pck1-c.8t to PC10BIOS.ROM and place it in a sub-folder named BIOS

Edit the “MAGICPCH.A22” file with a texteditor (Notpad++ for example) and change the name or something, just to start with. Keep in mind the amount of characters have to remain the same.

Go to NO$NES emulator and do the following
  •     Utility
  •     Assemble
  •     Open “MAGICPCH.A22”


The game will now start and you will see the custom instructions
Now you need to split MAGICPCH.NES file into multiple ROM files ( I don’t really have a proper way of doing this, but a HEX editor like notepad++ will do the job. You need to cut the last 8192 bytes, then cut the last 32 bytes from that file.