Sega System C

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The Sega System C is an arcade board used by Sega between 1989 and 1994 (though it was later used by Atlus for their Print Club series). A slight update called the Sega System C2 was introduced in 1990. The Columns manual claims the hardware was called Sega System 14.

Hardware

The System C hardware is built on top of the Sega Mega Drive with a few differences that make them incompatible:

• The 68000 is clocked at ~9Mhz. The Z80 was removed; the faster 68000 allows it to handle sound without slowdown in games.
• The VDP no longer uses its internal CRAM for palettes. Instead, it relies on external hardware to provide color information. The hardware is capable of producing 4096 possible colors which can be fed to the VDP in a variety of ways.

The System C2 adds a NEC µPD7759 ADPCM sample playback chip and a sample ROM which can be banked (as the chip can only access 128kB of samples at a time). This serves as a replacement for using the YM2612's DAC for samples, and has the extra advantage of not needing to constantly provide sample data to the µPD7759 — the 68000 merely sets the sample ROM bank and writes a sample number to play. However, the µPD7759 can only play one sample at a time.

Technical Specifications

This hardware is based closely on the Sega Mega Drive/Genesis hardware, with the main CPU, sound processor and graphics processor being the same, but with the addition of the Altera EPM5032 and Sega 315-5242 color encoder increasing the color palette. The CPU clock speed is slightly faster (8.94 MHz instead of 7.67 MHz), there is no Z80, and the sound chip is driven by the CPU. The DAC is also replaced by the NEC µPD7759, the same as the System 16 hardware.

• Board composition: Single JAMMA board
• Main CPU: MC68000 @ 8.948862 MHz (16-bit & 32-bit instructions @ 1.566 MIPS)
• Sound chips: Yamaha YM3438 @ 7.670453, SN76496 @ 3.579545
• Optional sound chip: NEC µPD7759 @ 640 kHz (9-bit ADPCM @ 8 kHz sampling rate)
• Graphics chips: Yamaha YM7101 VDP, Altera EPM5032, Sega 315-5242 color encoder
• Video resolution: 320×224 pixels
• Color palette: 98,304
  • Sega's 16-bit arcade color palette: 15-bit RGB high color depth (32,768 colors) and 1-bit shadow & highlight that triples up to 98,304 colors.
• Colors on screen: 6144
• Hardware features: Line scroll, column scroll, raster interrupt, 2 background planes (one with an option window), sprite plane, several levels of priority

List of System C Games

• Bloxeed (1989)
• Columns (1990)
• Columns II (1990)

List of System C2 Games

Note: there are a number of other Print Club games omitted from this list because they are undiscovered/undumped/etc.

• Borench (1990)
• PotoPoto (1994)
• Print Club (1995)
• Print Club Vol.2: Winter Version (1995)
• Print Club Vol.4: Summer Version (1996)
• Print Club Vol.5: Autumn Version (1996)
• Puyo Puyo (1992)
• Puyo Puyo Tsuu (1994)
• Puzzle & Action: Ichidant-R (1994)
• Puzzle & Action: Tant-R (1992)
• Ribbit! (1992)
• SegaSonic Popcorn Shop (1993)
• Stack Columns (1994)
• Thunder Force AC (1990)
• Twin Squash (1991)
• Waku Waku Marine (1992)
• Zunzunkyou no Yabou (1994)

Sega arcade boards
Originating in arcades
77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 VIC Dual G80 Zaxxon VCO Object System 1 LaserDisc Appoooh Hang-On System 2 System 16 OutRun Gigas X Board Y Board System 24 System 18 System 32 Model 1 Model 2 H1 Board Model 3
Console-based hardware
84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 SG-1000 System E System C Mega-Tech System Mega Play Sega Titan Video NAOMI Hikaru NAOMI 2 Atomiswave System SP Chihiro Triforce
PC-based hardware
05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 Lindbergh Europa-R RingEdge RingWide RingEdge 2 Nu Nu 1.1 Nu 2 ALLS