The Components-Bin Strategy: Konami’s Contra
Again and again, I take a look at video games which can be a part of “programs”: the Sega System 1, the Hyper Neo Geo 64, the CAVE CV1000. However there ain’t no rule that claims you have to prepare your video games that manner. You may simply take no matter elements are most handy. The Panic Street board I constructed a pinball controller for is one instance. However Konami might be most related to this method. Let’s take Contra as a case examine.
Contra is an arcade sport?
Contra is an effective instance of a sport whose unique received utterly overshadowed by the theoretically technically inferior NES port. Truthfully I can see why; the NES pressured the sport to lose the bizarre vertical orientation and pastel colour schemes, and it desperately wanted some good co-op platformers. This model of the sport’s nonetheless a enjoyable play, although.
Arcade Contra is from 1987. I might say from a {hardware} standpoint, there’s nothing significantly state-of-the-art, but it surely’s nothing to sneeze at both. A number of scrolling tilemaps and sprites, 15-bit colour depth, and FM synth music. Admittedly, the degrees are a bit shorter than the NES model.
So, how did Konami put this sport collectively? System16.com reviews a “Contra-based {hardware}” household, however as we’ll see, it’s solely a really unfastened time period.
The board
Right here it’s: the Konami GX633 motherboard, used for Contra and nothing else. Except you depend Gryzor as a special sport, which you actually shouldn’t. (Searching for Probotector? That title was a console unique)
The CPU powering the present is the Hitachi 6309. Hitachi took Motorola’s well-regarded 6809, used within the Vectrex amongst different machines, and upgraded it to CMOS, in addition to including some good efficiency enhancements. You’ll be able to consider it because the V20 to the 6809’s 8088. Talking of the 6809, Konami used a kind of because the secondary sound CPU, additionally manufactured by Hitachi.
Have a look under to CPU to see a chip whose label is scratched off right here. That’s the Yamaha YM2151 FM synthesizer, used within the well-known DX100 synth. Why it (and what I presume is its DAC) have had their surfaces scratched off is past me; I’m undecided if that is one thing Konami did or one thing else that occurred to this board over its lengthy life.
Talking of audio; that is truly a stereo sport! You select both stereo or mono based mostly on the loopback connector’s place in CN3 or CN4; proper now it’s in mono, however after I received it it was set to stereo; stereo sound is output via the CN2 connector, which has had its wires reduce. One in every of as of late I ought to wire up some RCA jacks to that connector; stereo sound on arcade boards is just not widespread on this period.
Twin movies once more
This stunning massive chip is the Konami 007121. (Konami customized chips typically have a numeric code starting with two zeroes) This can be a fairly first rate tilemap and sprites graphics chip, used within the following video games:
- Fight College
- Quick Lane
- Flak Assault
- Contra (clearly)
- Haunted Fort
- Trick Entice
Actually, I’m fairly positive the presence of the Konami 007121 is what System16 is utilizing to outline because the “Contra-based {hardware}”. Nevertheless it’s value noting that not each sport that used the Konami 007121 used it in the identical configuration. For instance, Contra has two of them.
This can be a lot just like the SuperGrafx or the Sega System E; the distinction is that that is just about par for the course for Konami. Notice that very like the System E, I don’t imagine there’s as a lot precedence management because the SuperGrafx. How the layers are drawn doesn’t fluctuate. It doesn’t must; this can be a machine that simply must play one sport.
We’ll wrap up the video circuitry with the Konami 007593. That is one other Konami half that was utilized in a number of locations; right here, it serves primarily as a video DAC. MAME claims it additionally has some I/O functionality that isn’t used right here. In any case, jammarcade.net has completed some reverse engineering right here to provide reproductions.
And sure, Konami did really feel the necessity to lengthen their 00xxxx codes to the resistor packs, labeled 005273. I assume these opaque elements codes have been meant no less than partially to make issues somewhat more durable for bootleggers. Certain, you may’t cease them, however you may sluggish them down.
Yet one more factor
Look simply to the precise of the 6309 CPU within the nook: right here’s one other Konami customized chip, the 007452. It’s additionally labeled the VRC&DMP, and even higher, furrtek has already completed a really deep evaluation of it, together with decapping. The 007452 has some neat multiplication and division performance; the 6809 has a {hardware} MUL opcode, and furrtek reviews that the 007452’s multiply performance isn’t utilized by Contra; solely its division.
It additionally has bankswitching performance; given the title VRC corresponds with the VRC sequence of mappers Konami utilized in Japan, that’s most likely what this a part of the “VRC&DMP” title means. In that case, VRC stands for Digital ROM Controller; if I needed to guess, I’d assume DMP stands for Division and Multiplication Processor, however who is aware of. Furrtek’s work made it into MAME 0.231 in 2021, making the 3D phases in Contra just a bit more durable.
Why
So, why did Konami do that? Your guess is nearly as good as mine; possibly they most well-liked the flexibleness for builders over the flexibleness of gross sales. A giant benefit of the “System” setup that firms like Sega used is {that a} flop may simply be transformed into a much bigger vendor; within the case of the System 16 and the System E, most likely Tetris. Had Contra been a flop, Konami may’ve reused some elements, however the circuitboards could be ineffective.
However there have been different advantages to Konami’s method past programmer flexibility. Right here’s Haunted Fort, one other Konami sport that used twin 007121 graphics chips. An enterprising pirate may wish to convert Contra to this sport; both as a result of it’s 1988 and it’s the recent title, or it’s 2023 and Haunted Fort didn’t promote very properly (it’s not nice) however is related to a well-known sequence, so goes for far more cash on the aftermarket. Effectively, too dangerous– Haunted Fort might use the identical graphics chip, but it surely makes use of totally different Konami sound chips and a Konami-customized CPU. Safety even right this moment.
