Oliver Achten's PC10 BIOS/NES to PC10 adapter

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Oliver Achten's PC10 BIOS/NES to PC10 adapter
by on (#2655)
Has anyone successfully built a 72-pin to PC10 adapter and booted a standard NES cart on a PC10, using Achten's BIOS? I've been unable to find the necessary pinouts to make the adapter, and Oliver Achten didn't respond to my e-mail asking for info. (The file's old enough that I wouldn't be surprised if his contact info is no longer current.) Any help would be greatly appreciated.

by on (#2667)
Damn, I never heard of such an adapter project, but the benefits would be great: pure RGB NES. I saw a guy that hacked a PC10 PPU into his NES for some RGB goodness.

by on (#2670)
Yeah, that's one of the nice parts.
The address and data pins are obvious enough, and I think I've gotten most of the others, it's just a few that I'm uncertain about.
Interestingly, the PC10 appears to have the Famicom sound pin that's missing on the NES; good to know in case I happen upon any Famicom carts in the future. (Or decide to wire a FDS into the thing.)

by on (#2681)
FDS, PC10?

Now that would have been awesome!

Oh how I wish the FDS came to the US, it would have been called the NDS (Nintendo Disk System, not Nintendo DS).

You could put your Famicom Disk in the PC10, and either play it or rewrite a new game.
Preliminary adapter/pinout/whatever
by on (#2786)
Here's what I have so far. Sorry about the alignment on the right side.
(The two previous guest posts are mine, btw.)
Edit: Second update.
Code:
NES to PC10 connections
By Kufat (kufat(a)hvc.rr.com)
Adapted from Kevin Horton's NES pinout (khorton@iquest.net)
This design has not been tested yet.


                             Top           Bottom
                         ----------------------------


                                  +-------+
*32                           GND |01   37| CLK 21.47727Mhz (NTSC) NC
A25                       PRG A11 |02   38| M2            A21
A24                       PRG A10 |03   39| PRG A12         A26
A23                        PRG A9 |04   40| PRG A13          A27
A22                        PRG A8 |05   41| PRG A14                A28   
C30                        PRG A7 |06   42| PRG D7         B23
C29                        PRG A6 |07   43| PRG D6         B24
C28                        PRG A5 |08   44| PRG D5         B25
C27                        PRG A4 |09   45| PRG D4         B26
C26                        PRG A3 |10   46| PRG D3         B27
C25                        PRG A2 |11   47| PRG D2         B28
C24                        PRG A1 |12   48| PRG D1         B29
C23                        PRG A0 |13   49| PRG D0         B30
B22                       PRG R/W |14   50| PRG /CE (/A15 & /M2)   B21
C22                          /IRQ |15   51| EXP 9         NC
NC                          EXP 0 |16   52| EXP 8         NC
NC                          EXP 1 |17   53| EXP 7         NC
NC                          EXP 2 |18   54| EXP 6         NC
NC                          EXP 3 |19   55| EXP 5         NC
NC                          EXP 4 |20   56| CHR /WR         A19
A20                       CHR /RD |21   57| CIRAM /CE         C12
C13                     CIRAM A10 |22   58| CHR A13         A18
C15                        CHR A6 |23   59| CHR A7         C14
C16                        CHR A5 |24   60| CHR A8         A13
C17                        CHR A4 |25   61| CHR A9         A14
C18                        CHR A3 |26   62| CHR A11         A16
C19                        CHR A2 |27   63| CHR A10         A15
C20                        CHR A1 |28   64| CHR A12         A17
C21                        CHR A0 |29   65| CHR /A13         B12
B20                        CHR D0 |30   66| CHR D7         B13
B19                        CHR D1 |31   67| CHR D6         B14
B18                        CHR D2 |32   68| CHR D5         B15
B17                        CHR D3 |33   69| CHR D4         B16
NC                       SECURITY |34   70| SECURITY         NC
NC                       SECURITY |35   71| SECURITY         NC
*31                           +5V |36   72| GND           *32
                                  +-------+

Notes:
A30 is the Famicom-only sound pin.
C2-C10, A7-A10, B4-B11, and others are used by the game selection subsystem.
A/B/C on 31 and 32 are all VCC and all ground respectively.

by on (#2837)
Won't it refuse to boot wihout the security chips connected?

by on (#2838)
If the PC10 requires security chips on its 'game cards' (which I don't think it does), they certainly would NOT be compatible with the ones in consumer NES cartridges; besides, the lockout chips on NES carts are there ONLY to prevent the NES console itself from constantly resetting - they could have been wired to disable the ROM if no chip was detected in the console itself (and the CIC patent apparently describes exactly this), but for whatever reason, Nintendo decided not to do that.

by on (#2850)
Quietust wrote:
[CIC chips in NES carts] could have been wired to disable the ROM if no chip was detected in the console itself (and the CIC patent apparently describes exactly this), but for whatever reason, Nintendo decided not to do that.

Nintendo eventually did that in Super NES games using the SA-1 chip (Super Mario RPG; Kirby Super Star).

by on (#2851)
The PC10 does require its own security chips. There are two options for dealing with this:

1. Use OA's PC10 BIOS and make the PC10 to NES adapter from scratch. This will completely bypass all security, but will disable the display of game names and instructions for legitimate PC10 games where they're present.

2. Make the PC10 to NES adapter out of a PC10 cart, and leave the Z80 sections intact. The cartridge in the adapter will show up as whatever the PC10 game was; it and all other PC10 games will still display their instructions. The security ROMs are interchangeable between carts; no checksumming is done. I intend to use this method so that the instructions will show up and because I don't have easy access to EPROMs or an EPROM programmer.

by on (#2852)
By your description, the PC10 does not use a security chip as the NES does - it simply uses a (possibly signed) descriptor ROM. Without that ROM, the BIOS program doesn't know what game is plugged into the slot (or that a game is even plugged in at all!) and treats it as empty.

by on (#2860)
The security rom/chip appears to be distinct from the instruction/ID ROM, although I'm not at all certain of that. It's definitely nothing like the NES sysem, though.
Any Luck?
by on (#3092)
Any luck on your tests building this apdater?

by on (#3093)
I won't be getting my PC10 until late August or early September; I'm picking it up on my way back to school in the fall.

by on (#3139)
Cool, I look forward to seeing your progress.