The evolution of the Super Nintendo motherboard

# The evolution of the Super Nintendo motherboard Source: [https://fabiensanglard.net/snes_mobos/index.html](https://fabiensanglard.net/snes_mobos/index.html) April 8, 2024 The evolution of the Super Nintendo motherboard --- Over the impressive lifespan of its 16\-bit machine \(12 years[\[1\]](https://fabiensanglard.net/snes_mobos/index.html#footnote_1)\), Nintendo produced twelve versions of the motherboard\. What is noteworthy is how they managed to reduce the number of chips necessary over time\. Looking at a summary table may seem like it is a daunting task to make sense of all of it\. NTSC Motherboards19901991199219931994199519961997SHVC\-CPU\-01SNS\-CPU\-GPM\-01SNS\-CPU\-GPM\-02SNS\-CPU\-RGB\-01SNS\-CPU\-RGB\-02SNS\-CPU\-APU\-01SNS\-CPU\-1CHIP\-01SNS\-CPU\-1CHIP\-02SNS\-CPU\-1CHIP\-03SNN\-CPU\-01PAL Motherboards19901991199219931994199519961997SNSP\-CPU\-01SNSP\-CPU\-1CHIP\-01SNN\-CPU\-01It is actually not that hard since most of the changes were minor updates\. There were only four major generation named Classic \(■\), APU \(■\), 1\-CHIP \(■\), and Junior \(■\)\. Classic --- The original Super Nintendo from 1990\-1992 had a lot of chips inside\. Count them and you will find fifteen\. The cartridge slot divides the system in two\. Above are the sound system processors and RAM[\[2\]](https://fabiensanglard.net/snes_mobos/index.html#footnote_2)[\[3\]](https://fabiensanglard.net/snes_mobos/index.html#footnote_3): - U10: OpAmp \(LM358\) - U11: Measure against erroneous issues at power on/off \(T529D\) - U13: Audio Processor: S\-SMP \(Sony SPC\-700\) - U14: Audio DSP: S\-DSP - U15, Audio ARAM 32KiB SRAM \(MCM51L832F10\) - U17: Audio D/A Converter: NEC PD6376 - U18: Audio Panasonic Operational Amplifiers Below the cartridge slot are the CPU/PPU sub\-systems and their RAM: - U1: S\-CPU \(Ricoh 5A22\) - U2: S\-PPU1 - U3: S\-PPU2 - U4: PPU RAM: 32KiB SRAM \(Victronix NV44256S\-10LL\) - U5: PPU RAM: 32KiB SRAM \(Victronix NV44256S\-10LL\) - U6: CPU S\-WRAM: 128 KiB SRAM - U7: RGB Encoder \(BA6592F S\-ENC\)\. Converts RGB into S\-Video and Composite - U8: CIC Copy\-protection \(F411A\) - U9: Reset / CIC circuit: \(74HCU04\) Notice in U12, this is not a chip but a \+5V Regulator \(7805\)\. This little guy is present on every version of the SNES\. APU --- The APU version of the SNES brings down the chip total to twelve\. This version is also sometimes referenced as "3\-CHIP"\. The Nintendo developer documentation mentioned a logical Audio Processing Unit[\[4\]](https://fabiensanglard.net/snes_mobos/index.html#footnote_4), made of a S\-SMP chip and a DSP chip\. With this version, the two are fused into an actual chip labeled "APU"\. Top part \(audio\): - U7: S\-RGB \(BA6592F\), Converts RGB into S\-Video and Composite - U10: Sound mixer \(S\-MIX\) - U13: ASIC APU \(S\-SMP \+ S\-DSP\) - U14: DAC \(6379a\) Bottom part \(cpu \+ graphics\): - U1: S\-CPU \(Ricoh 5A22\) - U2: S\-PPU1 - U3: S\-PPU2 - U4: PPU RAM: 32KiB SRAM - U5: PPU RAM: 32KiB SRAM - U6: CPU S\-WRAM: 128 KiB SRAM - U7: RGB Encoder \(SEC\) - U8: CIC - U9: Reset / CIC circuit Notice the oscillator \(left of red thingy in X1\) and resonator \(blue thingy in X2\) we studied last week\. These two will be the only unchanged components through the whole console lifetime\. 1\-CHIP --- With the 1\-CHIP version, Nintendo took a giant step forward to fuse the CPU and the two PPU into a single ASIC\. This motherboard brings down the total number of chips to nine\. Top part \(audio\): - U2: ASIC APU \(S\-SMP \+ S\-DSP\) - U6: DAC \(6379a\) - U7: S\-RGB \(BA6592F\), Converts RGB into S\-Video and Composite - U10: Sound mixer \(S\-MIX\) Bottom part \(audio\): - U1: ASIC with CPU \+ PPU1 \+ PPU2 - U3: CPU S\-WRAM: 128 KiB SRAM - U4: VRAM 32KiB - U5: VRAM 32KiB - U8: CIC \(F411B\) The red thingy is gone, the red variable capacitor is likely moved to the back of the mobo\. Jr --- The Super Nintendo Jr \(also called Mini\) is the final form of the SNES\. Only nine chips remain\. The top and bottom part no longer are dedicated to a specific sub\-system\. Top part: - U6: Audio D/A Converter: 6379A - U7: S\-RGB - U8: CIC - U10: S\-MIX Bottom part: - U1: ASIC with CPU \+ PPU1 \+ PPU2 - U2: ASIC APU with S\-SMP \+ S\-DSP - U3: S\-WRAM - U4: VRAM 32KiB - U5: VRAM 32KiB Notice how the blue resonator \(in X2\) has managed to survive all this\. So did the oscillator \(in X1\)\. Which one was the best? --- The retro community has established guidelines[\[5\]](https://fabiensanglard.net/snes_mobos/index.html#footnote_5)[\[6\]](https://fabiensanglard.net/snes_mobos/index.html#footnote_6)to help enthusiasts buy the right console for themselves\. From failure rate to video output quality, everything is detailed on[consolemods\.org SNES Wiki](https://consolemods.org/wiki/SNES:SNES_Mods_Wiki)\. References --- [^](https://fabiensanglard.net/snes_mobos/index.html#back_1)\[1\]Introduced in 1991 in Japan, last produced in 2003\.[^](https://fabiensanglard.net/snes_mobos/index.html#back_2)\[2\][SNES motherboards chips reference](https://wiki.console5.com/wiki/SNES)[^](https://fabiensanglard.net/snes_mobos/index.html#back_3)\[3\][SNES & N64 Video Encoder Information/Datasheets](https://nfggames.com/forum2/index.php?topic=3525.0)[^](https://fabiensanglard.net/snes_mobos/index.html#back_4)\[4\][SNES Development Manual, fig 2\-22\-1](https://archive.org/details/SNESDevManual/book1/page/n97/mode/2up)[^](https://fabiensanglard.net/snes_mobos/index.html#back_5)\[5\][SNES Buying Guide](https://consolemods.org/wiki/SNES:Buying_Guide)[^](https://fabiensanglard.net/snes_mobos/index.html#back_6)\[6\][SNES Model Differences](https://consolemods.org/wiki/SNES:SNES_Model_Differences) --- \*