Search found 38 matches

by coto
Tue Jun 02, 2020 11:12 pm
Forum: Other Retro Dev
Topic: Programming hints from Alan Turing (Mark I/II)
Replies: 4
Views: 204

Re: Programming hints from Alan Turing (Mark I/II)

Heh if there existed people able to talk to birds or to play around with wireless electricity makes me wonder why can't we yet even understand the human brain. I get the feeling most inventions were just an accidental out of pre-discovery I was amazed people creating video games, or smart programs t...
by coto
Tue Jun 02, 2020 12:09 pm
Forum: Other Retro Dev
Topic: Programming hints from Alan Turing (Mark I/II)
Replies: 4
Views: 204

Re: Programming hints from Alan Turing (Mark I/II)

Some time ago I found link to programming manual from 1951 year for one of the first british computers - Manchester/Ferranti Mark I/II and author was Alan Turing himself: http://curation.cs.manchester.ac.uk/computer50/www.computer50.org/kgill/mark1/RobertTau/turing.pdf There is interesting chapter ...
by coto
Thu May 28, 2020 9:46 pm
Forum: SNESdev
Topic: New SNES game: Yo-Yo Shuriken [Cartridge+ROM]
Replies: 7
Views: 6246

Re: New SNES game: Yo-Yo Shuriken [Cartridge+ROM]

I've just published a long article about making my SNES game Yo-Yo Shuriken . It starts with the various steps I went through to design and program the game. Then, it details how we manufactured new cartridges (with box and manual) for a console whose commercial support ceased more than 20 years ag...
by coto
Sat May 23, 2020 11:13 pm
Forum: General Stuff
Topic: SNES Doom development, Randy Linden
Replies: 12
Views: 957

Re: SNES Doom development, Randy Linden

GSU related stuff I have most of these read from online resources, reverse engineered a bit of it, and also looked at source code (be it verilog or C). Of course i'm no expert at it, but I do understand quite a bit of it, enough to make an implementation and to point out what does what. How familiar...
by coto
Sat May 23, 2020 5:37 pm
Forum: General Stuff
Topic: SNES Doom development, Randy Linden
Replies: 12
Views: 957

Re: SNES Doom development, Randy Linden

AFAIK the binary space partitioning simply helps with determining which sectors are visible from any given point in the map. Also, if this was a side effect of the BSP, this glitch would be present in other Doom versions, and I've never noticed it anywhere else. Randy Linden apparently didn't even ...
by coto
Sat May 23, 2020 9:24 am
Forum: General Stuff
Topic: SNES Doom development, Randy Linden
Replies: 12
Views: 957

Re: SNES Doom development, Randy Linden

I wonder what the game is doing to determine which texture columns to use, and why that changes depending on the angle the player is facing. Was that a mistake or a deliberate decision made for performance reasons? It would be cool if I could figure that out from looking at the source code. I think...
by coto
Fri May 22, 2020 5:27 pm
Forum: General Stuff
Topic: SNES Doom development, Randy Linden
Replies: 12
Views: 957

SNES Doom development, Randy Linden

https://www.youtube.com/watch?v=P5PknJvplKg

Randy Linden interview about Doom Snes port and the SuperFX / GSU co-processor

Nonetheless it's something fascinating.
by coto
Sat May 16, 2020 12:16 pm
Forum: SNESdev
Topic: Differences of SPCPlayer and SPC7000
Replies: 4
Views: 364

Re: Differences of SPCPlayer and SPC7000

Thank you guys! So it is safe to assume, that the SPCplayer, contains the implementation of the SPC7000? Usually a SPC Player is just an API for the lower level components, so it relies on these, otherwise you may have to maintain 2 different SPC Cores (one for the SNES FPGA and the other the SPC P...
by coto
Thu May 14, 2020 10:17 am
Forum: SNESdev
Topic: Differences of SPCPlayer and SPC7000
Replies: 4
Views: 364

Re: Differences of SPCPlayer and SPC7000

I want to replicate a subset of the SNES system on an FPGA, specifically, the audio subsystem. I found out this repository. https://github.com/srg320/FpgaSnes/tree/master/FPGA As you can see, there is a directory called SPC Player, and another called SPC7000. Do you know the difference? are both ne...
by coto
Wed May 13, 2020 12:27 pm
Forum: NESdev
Topic: Compiled stack proposal
Replies: 22
Views: 1479

Re: Compiled stack proposal

Hisoft C is C compiler with 24Kb core within target machine (ZX Spectrum 48). And it's source code for stdlib library is really cool: /*****************************/ /* Hisoft C */ /* Standard Function Library */ /* HEADER */ /* */ /* Copyright (C) 1984 Hisoft */ /* Last changed 15 Aug 1985 */ /***...
by coto
Thu May 07, 2020 1:21 pm
Forum: NESdev
Topic: Linear interpolation overtones
Replies: 10
Views: 1115

Re: Linear interpolation overtones

Thank you for the answers. I am using unsigned 8-bit PCM, which is lsr-d once to discard the lowest bit that can't fit in the $4011 register. These are summed and divided by 2, I will post the relevant code later. (The next improvement is to add compatibility with the output of my external pre-proc...
by coto
Wed May 06, 2020 8:19 pm
Forum: NESdev
Topic: Linear interpolation overtones
Replies: 10
Views: 1115

Re: Linear interpolation overtones

The interpolated samples are a sum and division by 2 of the last, and the next output sample from ROM. I know it's NES related and this response is somewhat more general but: Does the PCM sounds OK without the interpolation? Is it signed PCM16? signed/unsigned PCM8? how many channels? To add interp...
by coto
Tue May 05, 2020 9:54 pm
Forum: General Stuff
Topic: Nintendo legacy console leak
Replies: 5
Views: 991

Re: Nintendo legacy console leak

For I, will never resort to ninty SDK/licensed program code resources of any sorts as some kind of guidance. There is enough info available in the internet to build apps/games for older platforms, even more nowadays because of the open source code. As for reverse engineering things, I guess it's tru...
by coto
Fri May 01, 2020 8:02 pm
Forum: Other Retro Dev
Topic: 3DS reverse engineering
Replies: 270
Views: 141244

Re: 3DS reverse engineering

I have tried the write to "GPUREG_START_DRAW_FUNC0" and indeed it fixes the hang. Meanwhile i have added GPU rendering to my AGB FIRM and scaling with linear interpolation. Looks pretty sick. I hardcoded the GPU cmd lists currently but eventually a port of citro3d should be done. Before this i also...