https://forum.freeplaytech.com/ Fri, 05 Jun 2026 21:11:46 +0000 MyBB https://forum.freeplaytech.com/showthread.php?tid=5511 Mon, 01 Jun 2026 09:12:54 +0000 Ahchay]]> https://forum.freeplaytech.com/showthread.php?tid=5511

Horatio Goes Snowboarding - second in my line of demakes of the Infinite State Games back catalog

Horatio Goes Snowboading for Neo Geo Pocket Color by Chris ahchay]]>

Horatio Goes Snowboarding - second in my line of demakes of the Infinite State Games back catalog

Horatio Goes Snowboading for Neo Geo Pocket Color by Chris ahchay]]> https://forum.freeplaytech.com/showthread.php?tid=5510 Fri, 15 May 2026 15:13:51 +0000 Ahchay]]> https://forum.freeplaytech.com/showthread.php?tid=5510 underscore42/ngpc-asteroids-neo: Homebrew Game for Neo Geo Pocket - ASTEROIDS neo

Decent effort at an asteroids clone there ]]> underscore42/ngpc-asteroids-neo: Homebrew Game for Neo Geo Pocket - ASTEROIDS neo

Decent effort at an asteroids clone there ]]> https://forum.freeplaytech.com/showthread.php?tid=5507 Fri, 27 Mar 2026 09:47:44 +0000 sodthor]]> https://forum.freeplaytech.com/showthread.php?tid=5507 https://www.reddit.com/r/EmuDev/comments...color_dev/]]> https://www.reddit.com/r/EmuDev/comments...color_dev/]]> https://forum.freeplaytech.com/showthread.php?tid=5501 Wed, 05 Nov 2025 18:58:19 +0000 NeoGeoFreak2004]]> https://forum.freeplaytech.com/showthread.php?tid=5501 PS: this is using sodthor's (huge shoutout to him for making the tools) conversion tools btw.

  How to convert videos for the NeoGeo Pocket Color.pdf (Size: 63.13 KB / Downloads: 5) ]]> PS: this is using sodthor's (huge shoutout to him for making the tools) conversion tools btw.

  How to convert videos for the NeoGeo Pocket Color.pdf (Size: 63.13 KB / Downloads: 5) ]]> https://forum.freeplaytech.com/showthread.php?tid=5499 Tue, 16 Sep 2025 21:00:50 +0000 Ahchay]]> https://forum.freeplaytech.com/showthread.php?tid=5499
It's a demake of the excellent DDMR by infinite state games - a cracking game if you're not aware of it, sort of a pacifist robotron

Dev has flown by and this has taken less than two weeks - roped in Mike from ISG for the music and sfx and I think you'll like the end result

The release candidate is on my website at https://ahchay.com/NGPC/index.html?blogid=Projects

Would appreciate any feedback you lot might have

  t90p7t0oppiw.png (Size: 15.29 KB / Downloads: 3) ]]>
It's a demake of the excellent DDMR by infinite state games - a cracking game if you're not aware of it, sort of a pacifist robotron

Dev has flown by and this has taken less than two weeks - roped in Mike from ISG for the music and sfx and I think you'll like the end result

The release candidate is on my website at https://ahchay.com/NGPC/index.html?blogid=Projects

Would appreciate any feedback you lot might have

  t90p7t0oppiw.png (Size: 15.29 KB / Downloads: 3) ]]> https://forum.freeplaytech.com/showthread.php?tid=5423 Tue, 16 May 2023 19:47:48 +0000 winteriscoming]]> https://forum.freeplaytech.com/showthread.php?tid=5423
This new version of vgmlib and z80 driver were made to support the T6W28 VGM files output from Furnace.

My experience with Furnace leads me to believe it is accurately replicating the sounds you can expect from a real NGPC with headphones.  Emulators don't necessarily do as good of a job.  I like to use vdmgr as my emulator, and it does ok with this sound driver, but doesn't sound quite accurate.

https://github.com/winteriscomingpinball...ngpc-t6w28

More details are in the repository.]]>
This new version of vgmlib and z80 driver were made to support the T6W28 VGM files output from Furnace.

My experience with Furnace leads me to believe it is accurately replicating the sounds you can expect from a real NGPC with headphones.  Emulators don't necessarily do as good of a job.  I like to use vdmgr as my emulator, and it does ok with this sound driver, but doesn't sound quite accurate.

https://github.com/winteriscomingpinball...ngpc-t6w28

More details are in the repository.]]> https://forum.freeplaytech.com/showthread.php?tid=5321 Mon, 11 Apr 2022 13:47:30 +0000 NeoGeoFreak2004]]> https://forum.freeplaytech.com/showthread.php?tid=5321 https://forum.freeplaytech.com/showthread.php?tid=5300 Tue, 08 Feb 2022 20:39:16 +0000 winteriscoming]]> https://forum.freeplaytech.com/showthread.php?tid=5300
For me, this is a better sound/music solution than what has been previously publicly available.

https://github.com/winteriscomingpinball/vgmlib-ngpc

The repository contains the source for a simple example rom that shows how to setup and play the music.

The repository also contains a python script to convert SMS VGM output from Deflemask (or any SMS VGM file) to NGPC.  The files have to be tuned in order to sound correct on the NGPC because it runs at a different clock rate than the SMS.

Special thanks to sodthor, mic_, and Ivan Mackintosh, whose generous sharing of their source code and knowledge allowed me to get to where I am.

------------------------------
Update 5/16/2023 - I recommend using this one instead that supports tracks composed for the chip that is in the NGPC: https://forum.freeplaytech.com/showthread.php?tid=5423]]>
For me, this is a better sound/music solution than what has been previously publicly available.

https://github.com/winteriscomingpinball/vgmlib-ngpc

The repository contains the source for a simple example rom that shows how to setup and play the music.

The repository also contains a python script to convert SMS VGM output from Deflemask (or any SMS VGM file) to NGPC.  The files have to be tuned in order to sound correct on the NGPC because it runs at a different clock rate than the SMS.

Special thanks to sodthor, mic_, and Ivan Mackintosh, whose generous sharing of their source code and knowledge allowed me to get to where I am.

------------------------------
Update 5/16/2023 - I recommend using this one instead that supports tracks composed for the chip that is in the NGPC: https://forum.freeplaytech.com/showthread.php?tid=5423]]> https://forum.freeplaytech.com/showthread.php?tid=5171 Wed, 28 Oct 2020 11:36:28 +0000 sodthor]]> https://forum.freeplaytech.com/showthread.php?tid=5171
Oct 30: Updated with 2 versions Fast/Prec(ision)

Fast = same detail level as previous version but 3x faster (no asm, just use + instead of *)
Prec = 2x precision but still 30% faster than first version

Old version: Way too slow
Needs 4x speed at least (C -> ASM?)
but funny
based on: https://github.com/bquenin/mode7

  mode7.zip (Size: 170.23 KB / Downloads: 16) ]]>
Oct 30: Updated with 2 versions Fast/Prec(ision)

Fast = same detail level as previous version but 3x faster (no asm, just use + instead of *)
Prec = 2x precision but still 30% faster than first version

Old version: Way too slow
Needs 4x speed at least (C -> ASM?)
but funny
based on: https://github.com/bquenin/mode7

  mode7.zip (Size: 170.23 KB / Downloads: 16) ]]> https://forum.freeplaytech.com/showthread.php?tid=5160 Sat, 19 Sep 2020 15:31:38 +0000 winteriscoming]]> https://forum.freeplaytech.com/showthread.php?tid=5160

As I have been working on my platformer engine, I am moving in the direction of a metroid-vania style game with free exploration and backtracking.

Here is a demo of the current state.  There are some player animations yet to be done, and there are no NPCs or enemies yet.  Tile collision detection needs work.

I am still figuring out what I want to do with backgrounds.  I can either treat the 2nd scroll plane as another layer of map and tap into more palettes, or use it for hblank or parallax effects.  I could end up picking and choosing per room.

Music is a placeholder.  Tiles are a work in progress.  Music and tiles are original, though, with tiles in particular, I have drawn inspiration from Castelvania.

Colors are not optimized for a stock NGPC screen.  I will have to work on that.  They work well on a NGPC with backlit LCD replacement.

What works:
-Dynamic room sizes.  Some are vertically scrolling only, some are horizontal only, some are a combo, and some don't scroll at all since they're exactly the size of the screen.
-Quick switching between rooms/maps as you exit one and enter another.
-The castle that you're in front of at the beginning can be entered by pressing up in front of the doorway (this kind of exit is allowed but not used elsewhere)
-Side exits bring you into another room, and there can be multiple exits in a room.
-You can climb vines (though climbing animation needs to be done)
-Some platforms allow you to jump up through them and then push down/jump to jump back down.

We'll see how far I can take it.

  Platformer2Capture.PNG (Size: 8.55 KB / Downloads: 189)

  PLATFORMER2.zip (Size: 22.9 KB / Downloads: 11) ]]>

As I have been working on my platformer engine, I am moving in the direction of a metroid-vania style game with free exploration and backtracking.

Here is a demo of the current state.  There are some player animations yet to be done, and there are no NPCs or enemies yet.  Tile collision detection needs work.

I am still figuring out what I want to do with backgrounds.  I can either treat the 2nd scroll plane as another layer of map and tap into more palettes, or use it for hblank or parallax effects.  I could end up picking and choosing per room.

Music is a placeholder.  Tiles are a work in progress.  Music and tiles are original, though, with tiles in particular, I have drawn inspiration from Castelvania.

Colors are not optimized for a stock NGPC screen.  I will have to work on that.  They work well on a NGPC with backlit LCD replacement.

What works:
-Dynamic room sizes.  Some are vertically scrolling only, some are horizontal only, some are a combo, and some don't scroll at all since they're exactly the size of the screen.
-Quick switching between rooms/maps as you exit one and enter another.
-The castle that you're in front of at the beginning can be entered by pressing up in front of the doorway (this kind of exit is allowed but not used elsewhere)
-Side exits bring you into another room, and there can be multiple exits in a room.
-You can climb vines (though climbing animation needs to be done)
-Some platforms allow you to jump up through them and then push down/jump to jump back down.

We'll see how far I can take it.

  Platformer2Capture.PNG (Size: 8.55 KB / Downloads: 189)

  PLATFORMER2.zip (Size: 22.9 KB / Downloads: 11) ]]> https://forum.freeplaytech.com/showthread.php?tid=5147 Mon, 17 Aug 2020 19:51:02 +0000 sodthor]]> https://forum.freeplaytech.com/showthread.php?tid=5147
Here is a new sound library for ngpc, it's a free port of the PSGLIB (https://github.com/sverx/PSGlib)
It works a bit like the official one from snk: load driver and load music to z80 ram then play.
No SFX.
sources & demo rom attached.

thanks to WinterIsComing for help/comments/...

Edited: PCM playback added for SFX (8bit unsigned stereo PCM), thanks to mic_
09/04: z80 minimized

Thor

  psglib_test.zip (Size: 100.23 KB / Downloads: 6) ]]>
Here is a new sound library for ngpc, it's a free port of the PSGLIB (https://github.com/sverx/PSGlib)
It works a bit like the official one from snk: load driver and load music to z80 ram then play.
No SFX.
sources & demo rom attached.

thanks to WinterIsComing for help/comments/...

Edited: PCM playback added for SFX (8bit unsigned stereo PCM), thanks to mic_
09/04: z80 minimized

Thor

  psglib_test.zip (Size: 100.23 KB / Downloads: 6) ]]> https://forum.freeplaytech.com/showthread.php?tid=5136 Tue, 21 Jul 2020 19:59:56 +0000 winteriscoming]]> https://forum.freeplaytech.com/showthread.php?tid=5136
In the demo, press A to pause and resume the BGM, and B to alternate between SFX1 and SFX2.

I heavily referenced the VGM drivers from @mic_ and the documentation on sound written Ivan Mackintosh.  I also referenced documentation on the VGM standard, specifically with regards to SMS VGM data.  This mostly consists of PSG data writes (which can be sent right to the sound registers on the Z80) and wait commands.

I have made the Z80 driver so it is synchronous with the T900 vblank.  Each vblank, the T900 parses the VGM data, sends a frame of data to a couple of buffers in shared RAM, and pulses the Z80 so it will process the frame.  It seems to be fast enough for my purposes, as I do not notice slowdown in the game I am working on.

BGM and SFX can be composed in Deflemask SMS mode.


I am still learning the intricacies of PSG data and the 2 PSG sound registers on the Z80.  The driver and library still need refining, so I will wait to share the source until it's ready.

I have tested it successfully on real hardware.

  VGMTEST.zip (Size: 9.03 KB / Downloads: 7) ]]>
In the demo, press A to pause and resume the BGM, and B to alternate between SFX1 and SFX2.

I heavily referenced the VGM drivers from @mic_ and the documentation on sound written Ivan Mackintosh.  I also referenced documentation on the VGM standard, specifically with regards to SMS VGM data.  This mostly consists of PSG data writes (which can be sent right to the sound registers on the Z80) and wait commands.

I have made the Z80 driver so it is synchronous with the T900 vblank.  Each vblank, the T900 parses the VGM data, sends a frame of data to a couple of buffers in shared RAM, and pulses the Z80 so it will process the frame.  It seems to be fast enough for my purposes, as I do not notice slowdown in the game I am working on.

BGM and SFX can be composed in Deflemask SMS mode.


I am still learning the intricacies of PSG data and the 2 PSG sound registers on the Z80.  The driver and library still need refining, so I will wait to share the source until it's ready.

I have tested it successfully on real hardware.

  VGMTEST.zip (Size: 9.03 KB / Downloads: 7) ]]> https://forum.freeplaytech.com/showthread.php?tid=5116 Wed, 10 Jun 2020 01:25:47 +0000 shicky256]]> https://forum.freeplaytech.com/showthread.php?tid=5116


I attached the ROM image to this post, the source is here if anyone's interested. Here's a screenshot:


  sample.zip (Size: 4.93 KB / Downloads: 9) ]]>


I attached the ROM image to this post, the source is here if anyone's interested. Here's a screenshot:


  sample.zip (Size: 4.93 KB / Downloads: 9) ]]> https://forum.freeplaytech.com/showthread.php?tid=4819 Wed, 03 Apr 2019 15:51:25 +0000 Ahchay]]> https://forum.freeplaytech.com/showthread.php?tid=4819
There's no actual game yet - just a playground with a bunch of asteroids, a Qix and a rotating "sprite" that moves in a classic turn-left/right and thrust kind of fashion, but thought that you lot might enjoy seeing it.

I'm not really sure where I'm going with it - I think I could probably turn this into a reasonable Asteroids clone relatively quickly but for now I'm just playing with different bitmap effects.


  defenderoids.png (Size: 11.77 KB / Downloads: 17)

Source: https://github.com/Ahchay/Defenderoids.ngp

Rom Only: Defenderoids.ngp

edit: removed the velocity limiter on thrust as that wasn't working.]]>
There's no actual game yet - just a playground with a bunch of asteroids, a Qix and a rotating "sprite" that moves in a classic turn-left/right and thrust kind of fashion, but thought that you lot might enjoy seeing it.

I'm not really sure where I'm going with it - I think I could probably turn this into a reasonable Asteroids clone relatively quickly but for now I'm just playing with different bitmap effects.


  defenderoids.png (Size: 11.77 KB / Downloads: 17)

Source: https://github.com/Ahchay/Defenderoids.ngp

Rom Only: Defenderoids.ngp

edit: removed the velocity limiter on thrust as that wasn't working.]]> https://forum.freeplaytech.com/showthread.php?tid=4606 Wed, 18 Apr 2018 20:38:48 +0000 Ahchay]]> https://forum.freeplaytech.com/showthread.php?tid=4606 http://www.retrovideogamer.co.uk/ - will be featuring a whistlestop tour of the best, or most notable, homebrew releases.

I thought it would be nice to put a few bios of the devs in there - would any of you lot like to give me a few words to pad out your entry?


@Loic, @Shicky256, @SodThor? @Flavor?]]> http://www.retrovideogamer.co.uk/ - will be featuring a whistlestop tour of the best, or most notable, homebrew releases.

I thought it would be nice to put a few bios of the devs in there - would any of you lot like to give me a few words to pad out your entry?


@Loic, @Shicky256, @SodThor? @Flavor?]]>