Mail has been fixed; you should now be able to confirm your e-mail address, watch pages, and the like.
Please report any issues on Discord.

Gun & Frontier

From The Cutting Room Floor
Jump to navigation Jump to search

Title Screen

Gun & Frontier

Also known as: Gun Frontier (JP)
Developer: Taito
Publisher: Taito
Platform: Arcade (Taito F2 System)
Released internationally: January 1991


CodeIcon.png This game has unused code.
GraphicsIcon.png This game has unused graphics.
DebugIcon.png This game has debugging material.
LevelSelectIcon.png This game has a hidden level select.


Gun & Frontier is a shooter with a strange story about a 22nd century gold rush in space. Space pirates get involved, as they so often do, and it's up to the player and possibly the player's friend to stop them.

Debug Functions

Round Select

Stage & Select
Does this earlier '90s Taito game feature the Taito Code? Indeed it does:

  • Hold the Service Coin button until a "SERVICE SW ERROR" message pops up on the screen.
  • Then, press 1P Start (x3), Service Coin, 1P Start.

A stage select menu should pop up after starting a new game. Press 1P Up/Down to change the round and 1P Button 1 to start a new game. There's no code in the game to control the "Area" portion of this menu, so it's a bit odd that it's even listed.

Object Test Mode

GunFrontierArcObjectTest.png
Place the following cheat in MAME's gunfront.xml cheat file to access a debug function after the game boots:

  <cheat desc="Object Test Mode">
    <script state="run">
      <action>maincpu.mw@0143C6=0004</action>
      <action>maincpu.mw@0143C8=97A6</action>
    </script>
    <script state="off">
      <action>maincpu.mw@0143C6=0000</action>
      <action>maincpu.mw@0143C8=2192</action>
    </script>
  </cheat>

The user can press 1P Left/Right to change the color number, but it doesn't seem to do anything. There doesn't seem to be a way to load an actual object on this object test menu.

GunFrontierArcObjectTestM.png
There's a header for this menu that's never seen -- it's quickly overwritten by the HUD.

(Source: Original TCRF research)

Unused Graphics

Why doesn't anyone ever make a supermarine? Wait, wouldn't that just be a boat? Nevermind
The character graphics ROM still has the work-in-progress name for Battle Shark, for some reason. Sensuikan still means submarine!

(Source: Original TCRF research)

Error Handler Leftovers

Most of the standard 68000 exception vectors have entries in the exception vector table, but they all point to ROM space 0x0F00000. That ROM space might have been used by development hardware while the game was still being tested, but it's empty in the final game. This is identical to the dummied-out handlers in Battle Shark.

Vector Address
Bus Error 0xF00000
Address Error 0xF00014
Illegal Instruction 0xF00028
Zero Divide 0xF0003C
CHK Instruction 0xF00050
TRAPV Instruction 0xF00064
Privilege Violation 0xF00078
Trace 0xF0008C
Line 1010 Emulator 0xF0009A
Line 1111 Emulator 0xF0009A
(Source: Original TCRF research)