Viewing Issue Advanced Details
ID Category [?] Severity [?] Reproducibility Date Submitted Last Update
08148 DIP/Input Trivial Always Dec 12, 2021, 15:06 Dec 17, 2021, 09:40
Tester jkburks View Status Public Platform MAME (Official Binary)
Assigned To kmg Resolution Fixed OS Windows 10/11 (64-bit)
Status [?] Resolved Driver
Version 0.238 Fixed in Version 0.239 Build 64-bit
Fixed in Git Commit 6d9b8c9 Github Pull Request # #8964
Summary 08148: spacewar, spaceshp: Missing input for reset button
Description Cinematronics Space Wars has a reset button in the center of the control panel. It appears that this button was never hooked up in MAME. This button has an important game function, as there are many situations where the players are unable to continue and need to reset the playfield during play.

This should not be confused with a soft reset or hardware reset (F3 of Shift + F3). It is a button intended to be used by the players, not a power switch or operator-only input.

Input (this Machine) has no entry for the reset button
Steps To Reproduce 1. Add coins credits.
2. Select a beginner, intermediate, or expert game mode. (can’t be changed during game)
3. (optional) modify the game during play by pressing one or more modification buttons.
Some modifications do not affect the beginner game modes.

Press 5 5 5 5 to add 4 minutes of credit
Press numpad 1 to select Beginner Mode - Fast (no inertia)
Press numpad 2 to expand the playfield beyond the screen edges.

Fly your ship until fuel reaches single digits, then fly off the edge of the screen so that the ship will run out of fuel before it reappears on the opposite side of the screen. At this point you will not be able to see your ship and it will not reappear on the screen. Technically the other player can shoot your ship to end the round, but it is very difficult and involves a lot of luck or many missiles.

Similarly, it is possible to have 2 disabled ships drifting in space with no control and/or missiles if you choose an intermediate or expert mode with inertia.

In these circumstances the players would want to reset the playfield, not wait for time to expire and lose their game.
Additional Information Space Wars uses a time credit system, where each coin inserted adds units to the play time. The default DIP in MAME is 60 seconds, so inserting 4 coins gives 4 minutes of play for 2 players. There is no limit on lives, rather the gameplay continues until time runs out (or players add more credits/time to extend).

The player ships are limited to 18 missiles and 250 units of fuel per round. The round ends when one or both ships are destroyed, at which point the playfield resets and the ships respawn at random locations with full fuel and missiles, and the next round begins. Players earn 1 point by destroying the other ship. The player with the most points when time expires is the winner.

Pressing the forward button uses fuel at a set rate. When a ship runs out of fuel it will be unable to thrust, rotate, or use hyperspace. When the missiles reach 0 the player can no longer fire. The game includes partial damage from glancing shots or collisions that can cripple a ship. Crippled ships can often fire missiles, but not line up shots due to being immobilized.

Given these rules, there are many circumstances where the players will be unable to continue the round. Without a reset switch, they would be forced to wait for the credit / time to expire. A hardware reset / power cycle would cause the players to lose their score and credit / time.

For this reason, the cabinets are labeled with instructions. On the original Cinematronics variant it is printed on the marquee:
4. Ship missing, Frustrated, Etc, Press Reset.

The control panel reset button should remove both player ships and initiate a playfield reset, allowing the players to begin a new round with a new ship, full fuel and missiles, on the same credit.
Github Commit
Regression Version
Affected Sets / Systems spacewar, spaceshp
Attached Files
jpg file icon pic006.jpg (59,544 bytes) Dec 12, 2021, 15:07 Uploaded by jkburks
Space Wars control panel left
jpg file icon pic007.jpg (67,815 bytes) Dec 12, 2021, 15:08 Uploaded by jkburks
Space Wars control panel right
There are no relationship linked to this issue.
User avatar
Steve Coomber
Dec 12, 2021, 22:00
An excellent observation. It looks like the "Unknown" DIP switch actually performs the reset that you are describing. This should be a simple fix.
User avatar
Steve Coomber
Dec 14, 2021, 17:30
This has been resolved by kmg. Refer to commit: