Version differences: Difference between revisions

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Nintendo stopped incrementing version numbers after 2/1/3.
Nintendo stopped incrementing version numbers after 2/1/3.
There is no known method to programmatically detect 1-CHIP consoles (the known differences are graphical in nature).
See also:
* [[Errata]] for a list hardware bugs that affect multiple chip revisions




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Nintendo used 3 different DAC chips:
Nintendo used 3 different DAC chips:
* NEC µPD6376, in NTSC motherboards dated 1990-1994 (SHVC-SOUND, SNS-CPU-GPM-01, SNS-CPU-GPM-02, SNS-CPU-RGB-01)
* NEC µPD6376, in NTSC motherboards dated 1990-1994 (SHVC-SOUND, SNS-CPU-GPM-01, SNS-CPU-GPM-02, SNS-CPU-RGB-01)
* NEC 6376, in motherboards dated 1992 (SNSP-CPU-01, SNSP-CPU-02)
* NEC 6376, in PAL motherboards dated 1992 (SNSP-CPU-01, SNSP-CPU-02)
* NEC 6379A, in motherboards dated 1995 or 1997 (SNS-CPU-RGB-02, SNS-CPU-APU-01, SNS-CPU-1CHIP-02, SNN-CPU-01, SNSP-CPU-1CHIP-01, SNSP-CPU-1CHIP-02)
* NEC 6379A, in motherboards dated 1995 or 1997 (SNS-CPU-RGB-02, SNS-CPU-APU-01, SNS-CPU-1CHIP-02, SNN-CPU-01, SNSP-CPU-1CHIP-01, SNSP-CPU-1CHIP-02)


Motherboards with the NEC µPD6376 DAC have a slight audio imbalance.  Nintendo tied the 2 Vref pins to a single single 47μF capacitor, while the µPD6376 datasheet shows the 2 Vref pins are supposed to be connected to 2 separate capacitors.<ref>[https://consolemods.org/wiki/SNES:Audio_Balance_Fix ConsoleMods Wiki - SNES:Audio Balance Fix]</ref>
Consoles with the NEC µPD6376 DAC have a slight audio imbalance.  Nintendo tied the 2 Vref pins to a single single 47μF capacitor, while the µPD6376 datasheet shows the 2 Vref pins are supposed to be connected to 2 separate capacitors.<ref>[https://consolemods.org/wiki/SNES:Audio_Balance_Fix ConsoleMods Wiki - SNES:Audio Balance Fix]</ref>
 


== References ==
== References ==
* [https://wiki.console5.com/wiki/SNES Console5 Tech Wiki - SNES] - List of Chips, ICs and capacitors for the various SNES motherboards.
* [https://wiki.console5.com/wiki/SNES Console5 Tech Wiki - SNES] - List of Chips, ICs and capacitors for the various SNES motherboards.

Latest revision as of 23:18, 26 November 2024

Nintendo stopped incrementing version numbers after 2/1/3.

There is no known method to programmatically detect 1-CHIP consoles (the known differences are graphical in nature).


See also:

  • Errata for a list hardware bugs that affect multiple chip revisions


S-CPU

S-CPU (5A22-01)

RDNMI version: 1

Known bugs:

  • Crashes if a DMA finishes just before HDMA happens


S-CPU A (5A22-02)

RDNMI version: 2

This revision:[1]

  • Fixes the DMA/HDMA crash
  • Changes the S-WRAM refresh position
  • Changes the HDMA setup position


Known bugs:

  • A recent HDMA transfer with BBADn=0 can make a DMA transfer fail.


S-CPU B (5A22-02)

RDNMI version: 2

This revision:

  • Fixes the DMA failure after a recent BBADn=0 HDMA transfer bug


S-CPUN A (RF5A122)

RDNMI version: 2

Also known as 1-CHIP.

This revision:

  • Combines S-CPU, S-PPU1 and S-PPU2 onto a single IC


S-PPU1 (5C77-01)

STAT77 version: 1

There is only 1 known version of the S-PPU1.

It is unknown if the S-PPU1 in a 3-chip console is the same as the PPU1 in the S-CPUN A 1CHIP console.


S-PPU2

S-PPU2 (5C78-01)

STAT78 version: 1


S-PPU2 A (5C78-02)

STAT78 version: 2

This is the rarest revision of the S-PPU2.


S-PPU2 B (5C78-03)

STAT78 version: 3


S-PPU2 C (5C78-03)

STAT78 version: 3


S-CPUN A (RF5A122)

STAT78 version: 3

Also known as 1-CHIP.

Found in 1-CHIP and SNES Jr motherboards.

This revision:

  • Combines S-CPU, S-PPU1 and S-PPU2 onto a single IC
  • The DAC has been changed and the image is sharper.[2]
  • The INIDISP early read bug does not corrupt tile slivers.[3]


Known bugs:

  • Glitches on the first visible scanline on some games that extend VBlank with force-blank.[4]
  • Brightness DAC has large rise-time.[5]
  • Reports of ghosting
  • The output signal is too bright.[6]
  • The SNS-CPU-1CHIP-03 motherboard does not output a composite sync signal.[7]


Audio

SHVC-SOUND

The first revision of the SNES's motherboard had a separate SHVC-SOUND module.


On motherboard

In 1992 Nintendo moved the SHVC-SOUND chips onto the SNS-CPU-GPM-01 motherboard.

This revision replaces the S-DSP chip with the S-DSP A chip. Any differences between the two revisions are unknown.


S-APU

Found on SNS-CPU-APU-01 and 1CHIP motherboards, the S-APU combines the S-SMP, S-DSP and Audio-RAM into a single S-APU IC.

The S-APU fixes the S-SMP timer glitch.[8]


DAC

Nintendo used 3 different DAC chips:

  • NEC µPD6376, in NTSC motherboards dated 1990-1994 (SHVC-SOUND, SNS-CPU-GPM-01, SNS-CPU-GPM-02, SNS-CPU-RGB-01)
  • NEC 6376, in PAL motherboards dated 1992 (SNSP-CPU-01, SNSP-CPU-02)
  • NEC 6379A, in motherboards dated 1995 or 1997 (SNS-CPU-RGB-02, SNS-CPU-APU-01, SNS-CPU-1CHIP-02, SNN-CPU-01, SNSP-CPU-1CHIP-01, SNSP-CPU-1CHIP-02)

Consoles with the NEC µPD6376 DAC have a slight audio imbalance. Nintendo tied the 2 Vref pins to a single single 47μF capacitor, while the µPD6376 datasheet shows the 2 Vref pins are supposed to be connected to 2 separate capacitors.[9]

References

  1. ares source code, ares/ares/sfc/cpu/timing.cpp, by Near and ares team
  2. 1st-gen Super Famicom / SNES vs. Super Famicom Jr. / SNES Jr by Chris Covell
  3. INIDISP Register - INIDISP Early Read Glitch by undisbeliever
  4. Demon's Crest 1CHIP glitching comparison by eightbitminiboss (YouTube video)
  5. INIDISP Register - Brightness Delay by undisbeliever
  6. RetroRGB - SNES 1CHIP Brightness / Signal correction
  7. About ConsoleMods Wiki - SNES:SNES Model Differences
  8. Forum post: list of version differences by Near
  9. ConsoleMods Wiki - SNES:Audio Balance Fix