Midway/Namco 1981
The gameplay of Bosconian can best be described as Rally-X in deep space. your goal in Bosconian is to destroy the enemy bases, while avoiding the relentless pursuit of several different types of enemy ships, and avoiding the various obstacles in your way. Fortunately for you, your enemies can also be affected by running into obstacles, and cannot shoot you (although they do a more than adequate job of ramming you...) A round is cleared when all of the bases on the screen are gone. On the right of the playfield, there are several displays. The "condition" indicates the level of enemy activity in the area-green means you're clear, yellow means to be on the lookout, and red means that you're dead meat. You also have your radar, which will show your position on the map, where the enemy bases are, and also indicates incoming formation attacks. Most of this info also comes from various spoken phrases ("Alert, Alert", "Battle stations", "Spy ship sighted", etc.)
Your ship is capable of moving in eight different directions, and with each shot fires both forward and backward at the same time. You have no control over the speed of your ship, although it will get faster as you get into later rounds.
Asteroids are scattered around the playfield, and do not move. These are easily avoided and blasted out of the way, and will also be destroyed by collision with an enemy ship. Asteroids are worth 10 points apiece.
Cosmo-Mines stay in one place as do asteroids, but these make a larger explosion, which can be deadly if you destroy one at close range. On the other hand, they can also be used in this manner to take out several enemies at once, and an effective strategy using these mines is to steer a formation attack toward one of them, often taking out the entire formation at once. Cosmo-Mines are worth 20 points apiece.
I-Type missiles are the most common in the game. Usually these are fairly easy to take out, but beware if these start to accumulate. Make sure to be firing constantly to keep the fighters in check. I-Type missiles are worth 50 points apiece.
P-Type missiles are pretty much the same as the I-type fighters, but are slightly faster. Same caveats apply. P-Type missiles are worth 60 points apiece.
E-Type missiles are dispached by the Bosconian bases, and travel only in a straight line from there, albeit very quickly. In later rounds, these are also found in formation attacks, and their speed makes it difficult to hit all of them in a formation attack. E-Types are worth 70 points apiece.
R-Type fighters can travel only from left to right across the screen (but can move up and down in this path), but they can also be heavily armed, often accompanied by extra gunpods... Wait a minute here... Not only is this the wrong ROM, but the wrong emulator entirely! Never mind that one...
The spy ship will also appear on the screen from time to time (strangely enough, for something that's supposed to be a SPY ship, when it appears you recieve a verbal warning "Spy ship sighted"... go figure.) These ships don't do anything out of the ordinary, but are worth what's supposed to be a "mystery" value, according to the game's attract mode. In reality, I have never seen a spy ship with a point value other than 200 points.
The Bosconian bases are your main target. Once all of these are destroyed, you will move on to the next round. Unlike the other enemies in the game, the bases can shoot at you, and in later rounds can also launch E-type missiles at your ship. The bases can be destroyed in one of two ways. Each of the six gun turrets surrounding the base can be destroyed individually for 200 points apiece, and once all of them are destroyed, the base itself is also destroyed, which is worth 1,500 points. Alternately, the bases have a weak spot in the center of the base, where a single shot will destroy the ehtire base. After the first few rounds, a shield will be over this, and only when it is exposed (to launch a missile, for example) can this spot be hit.
Bosconian is run by three Z80 processors, and is able speak with digitized sound, unlike several other talking games of the day (such as Gorf and Wizard of Wor, which used speeh synthesis). As was mentioned before, this is very similar hardware to that of a Galaga machine, and this was the fate of many a Bosconian machine.
For more information, including technical information on Bosconian, an arcade collector by the name of Kevin Estep has put together this page which contains some additional pictures of the marquee and side panels, the DIP switch settings as well as some pictures of a Bosconian PCB.