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Back in 2002 a friend and I wanted to port Psycho Fox to the GBA, and so we started to hack the game to extract the data. We did not quite finish, but looking at my archives I believe it would not hurt publishing what we've got.

'pfviewer' is GBA code to display a level BG/FG (only, no enemies) of Psycho Fox. The version I've got compiled shows only 1 level, but if someone manage to recompile it (or hack the binary) it is easy to show all levels of the game. And at least some of the info are in the code.

The tables in data/ were extracted from Psycho Fox ROM. Unfortunately I can't find the 'pfexporter' program which did that job. However based on the data it should be easy to retrieve the offsets in the original ROM.

Some bits from my notes (sorry it's a mess):

RAM MAPPING

0xC00D    Country
0xC020    Level ($0-$15)
0xC021    World ($0-$6)
0xDF00-0xDFC0 Sprites shadow (40 Y then 40 Interleaved X/N)

Accesses of $C020 (Current Level):

Code @ $2421 read from table:

$5753 (21 addresses, one per level)
00005750: xxxx xx7d 579c 57bb 57ce 57ff 5720 5841 ...}W.W.W.W.W XA
00005760: 5856 586d 5880 5897 58b0 58b9 58dc 58f3 XVXmX.X.X.X.X.X.
00005770: 5818 5931 5940 595f 5982 59a7 59xx xxxx X.Y1Y@Y_Y.Y.Y...

Each address point to a list of EGGS CONTENTS.
The list is stopped using 0xFF.

Code @ $31A5 read from table:

$31E8
..

Code @ $3806 read from table:

$514C (21 addresses, one per level)
00005140: xxxx xxxx xxxx xxxx xxxx xxxx 7651 8751 ............vQ.Q
00005150: a051 a951 ba51 cb51 d451 9d52 4653 ef53 .Q.Q.Q.Q.Q.RFS.S
00005160: a854 e154 3255 4355 6455 3556 4656 5756 .T.T2UCUdU5VFVWV
00005170: 7856 b956 0a57 xxxx xxxx xxxx xxxx xxxx xV.V.W..........

Each address point to a list of OBJECTS CONTENTS.
The list is stopped using 0xFFFF.

Code @ $43AF read from table:

$50D8 (21 x 4 bytes)
000050d8: 3080 1100 Level 1-1
6980 1100 Level 1-2
000050e0: a280 1100 Level 1-3
db80 1100 Level 2-1
1481 1100 Level 2-2
4d81 1100 Level 2-3
000050f0: 3080 1100 Level 3-1
6980 1100 Level 3-2
a280 1100 Level 3-3
9881 1100 Level 4-1
00005100: d181 1100 Level 4-2
0a82 1100 Level 4-3
3080 1100 Level 5-1
6980 1100 Level 5-2
00005110: a280 1100 Level 5-3
db80 1100 Level 6-1
1481 1100 Level 6-2
4d81 1700 Level 6-3
00005120: db80 1100 Level 7-1
1481 1100 Level 7-2
4d81 1100 Level 7-3
8681 0500 Warp Zones
00005130: 9b81 0500
b081 0500
c581 0500
da81 0500
00005140: ef81 0500
0482 0500
1982 0500

Code @ $43EA

$4405
03 02 03
03 02 01
02 03 03
03 03 03
02 02 01
03 01 03
03 01 02
01 01 01 01 01 01 01 01
--> store in (C025h)
--> For each level, starting height in screen

Code @ $4FDE

Fetch from RAM at (A400h)
psychofox.sms.dat.40 is the currently mapped page at this moment.
A400h --> 2400h in page 4
28 * 2 bytes which are address to locations following the table.

MONSTERS LIST

Format:

screen number, screen position x, monster y, monster type

Monster types:

00 : Red Hopper
01 : Pockly Guy
02 : Gabacho
03 : Poota
04 : Bunbun Bee
05 : Zizo zizo
06 : Skull
07 : Fireball
08 : Boss (?)
...

For how the BG/FG is mapped, see the pfviewer source code.
Basically we've got a list of screen id, each screen refers to 2 half-screen id, each half-screen refers to 2 quarter-screen, each quarter-screen refers to 8 vertical strips of 16x16 metatiles, each metatiles refers to 4 tiles.

Sorry if it's messy. If someone is interested in hacking Psycho Fox at least this could help a bit. And, I probably can remember more if asked.

tile-library.png (32.09 KB)

pfviewer-20080809-omar.zip (88.31 KB)

Is there a way to use the source code to port Psycho Fox to the Mega Drive?

Well, you could use it to obtain the level data but not much more. The Mega Drive can already play it in SMS compatibility mode, so why bother?

If someone wants to port it to the Mega Drive, I think Magical Flying Hat Turbo Adventure might actually be a better starting point than the Master System game.

Maxim. is i wanted to make a homebrew port of psycho fox for the mega drive is what i mean is i wanted to know how to use psycho fox sms source code to port it to the mega drive like giving it mega drive grafics and features

It's possible but it is an enormous amount of work. Usually if you have to ask the question it means you may not have the experiment in hacking and assembly.

However as Kagesan mentioned, Magical Flying Hat Turbo Adventure is very close to Psycho Fox in term of engine and could possibly be reskined to look like Psycho Fox if someone published a tool to edit the game content.

Bock wrote

It's possible but it is an enormous amount of work. Usually if you have to ask the question it means you may not have the experiment in hacking and assembly.

However as Kagesan mentioned, Magical Flying Hat Turbo Adventure is very close to Psycho Fox in term of engine and could possibly be reskined to look like Psycho Fox if someone published a tool to edit the game content.

also im not just porting psycho fox to the sega genesis/sega mega drive
im all so porting it to the super famicom and the turbo grafix 16/pc engine

Author	Message
Bock Site Admin Joined: 08 Jul 2001 Posts: 8648 Location: Paris, France	Psycho Fox hacking Posted: Sat Aug 09, 2008 5:38 pm
	Back in 2002 a friend and I wanted to port Psycho Fox to the GBA, and so we started to hack the game to extract the data. We did not quite finish, but looking at my archives I believe it would not hurt publishing what we've got. 'pfviewer' is GBA code to display a level BG/FG (only, no enemies) of Psycho Fox. The version I've got compiled shows only 1 level, but if someone manage to recompile it (or hack the binary) it is easy to show all levels of the game. And at least some of the info are in the code. The tables in data/ were extracted from Psycho Fox ROM. Unfortunately I can't find the 'pfexporter' program which did that job. However based on the data it should be easy to retrieve the offsets in the original ROM. Some bits from my notes (sorry it's a mess): RAM MAPPING 0xC00D Country 0xC020 Level ($0-$15) 0xC021 World ($0-$6) 0xDF00-0xDFC0 Sprites shadow (40 Y then 40 Interleaved X/N) Accesses of $C020 (Current Level): Code @ $2421 read from table: $5753 (21 addresses, one per level) 00005750: xxxx xx7d 579c 57bb 57ce 57ff 5720 5841 ...}W.W.W.W.W XA 00005760: 5856 586d 5880 5897 58b0 58b9 58dc 58f3 XVXmX.X.X.X.X.X. 00005770: 5818 5931 5940 595f 5982 59a7 59xx xxxx X.Y1Y@Y_Y.Y.Y... Each address point to a list of EGGS CONTENTS. The list is stopped using 0xFF. Code @ $31A5 read from table: $31E8 .. Code @ $3806 read from table: $514C (21 addresses, one per level) 00005140: xxxx xxxx xxxx xxxx xxxx xxxx 7651 8751 ............vQ.Q 00005150: a051 a951 ba51 cb51 d451 9d52 4653 ef53 .Q.Q.Q.Q.Q.RFS.S 00005160: a854 e154 3255 4355 6455 3556 4656 5756 .T.T2UCUdU5VFVWV 00005170: 7856 b956 0a57 xxxx xxxx xxxx xxxx xxxx xV.V.W.......... Each address point to a list of OBJECTS CONTENTS. The list is stopped using 0xFFFF. Code @ $43AF read from table: $50D8 (21 x 4 bytes) 000050d8: 3080 1100 Level 1-1 6980 1100 Level 1-2 000050e0: a280 1100 Level 1-3 db80 1100 Level 2-1 1481 1100 Level 2-2 4d81 1100 Level 2-3 000050f0: 3080 1100 Level 3-1 6980 1100 Level 3-2 a280 1100 Level 3-3 9881 1100 Level 4-1 00005100: d181 1100 Level 4-2 0a82 1100 Level 4-3 3080 1100 Level 5-1 6980 1100 Level 5-2 00005110: a280 1100 Level 5-3 db80 1100 Level 6-1 1481 1100 Level 6-2 4d81 1700 Level 6-3 00005120: db80 1100 Level 7-1 1481 1100 Level 7-2 4d81 1100 Level 7-3 8681 0500 Warp Zones 00005130: 9b81 0500 b081 0500 c581 0500 da81 0500 00005140: ef81 0500 0482 0500 1982 0500 Code @ $43EA $4405 03 02 03 03 02 01 02 03 03 03 03 03 02 02 01 03 01 03 03 01 02 01 01 01 01 01 01 01 01 --> store in (C025h) --> For each level, starting height in screen Code @ $4FDE Fetch from RAM at (A400h) psychofox.sms.dat.40 is the currently mapped page at this moment. A400h --> 2400h in page 4 28 * 2 bytes which are address to locations following the table. MONSTERS LIST Format: screen number, screen position x, monster y, monster type Monster types: 00 : Red Hopper 01 : Pockly Guy 02 : Gabacho 03 : Poota 04 : Bunbun Bee 05 : Zizo zizo 06 : Skull 07 : Fireball 08 : Boss (?) ... For how the BG/FG is mapped, see the pfviewer source code. Basically we've got a list of screen id, each screen refers to 2 half-screen id, each half-screen refers to 2 quarter-screen, each quarter-screen refers to 8 vertical strips of 16x16 metatiles, each metatiles refers to 4 tiles. Sorry if it's messy. If someone is interested in hacking Psycho Fox at least this could help a bit. And, I probably can remember more if asked. tile-library.png (32.09 KB) pfviewer-20080809-omar.zip (88.31 KB)

brock3200 Joined: 24 Sep 2015 Posts: 17 Location: florida	Posted: Fri Oct 23, 2015 1:18 am
	Is there a way to use the source code to port Psycho Fox to the Mega Drive?

Maxim Site Admin Joined: 19 Oct 1999 Posts: 14734 Location: London	Posted: Fri Oct 23, 2015 1:06 pm
	Well, you could use it to obtain the level data but not much more. The Mega Drive can already play it in SMS compatibility mode, so why bother?

Kagesan Joined: 01 Feb 2014 Posts: 877	Posted: Fri Oct 23, 2015 4:14 pm
Kagesan Joined: 01 Feb 2014 Posts: 877	If someone wants to port it to the Mega Drive, I think Magical Flying Hat Turbo Adventure might actually be a better starting point than the Master System game.

brock3200 Joined: 24 Sep 2015 Posts: 17 Location: florida	Posted: Sun Oct 25, 2015 4:30 pm
	Maxim. is i wanted to make a homebrew port of psycho fox for the mega drive is what i mean is i wanted to know how to use psycho fox sms source code to port it to the mega drive like giving it mega drive grafics and features

Bock Site Admin Joined: 08 Jul 2001 Posts: 8648 Location: Paris, France	Posted: Sun Oct 25, 2015 9:30 pm
	It's possible but it is an enormous amount of work. Usually if you have to ask the question it means you may not have the experiment in hacking and assembly. However as Kagesan mentioned, Magical Flying Hat Turbo Adventure is very close to Psycho Fox in term of engine and could possibly be reskined to look like Psycho Fox if someone published a tool to edit the game content.

brock3200 Joined: 24 Sep 2015 Posts: 17 Location: florida	Posted: Sun Jan 03, 2016 5:57 pm
	Bock wrote It's possible but it is an enormous amount of work. Usually if you have to ask the question it means you may not have the experiment in hacking and assembly. However as Kagesan mentioned, Magical Flying Hat Turbo Adventure is very close to Psycho Fox in term of engine and could possibly be reskined to look like Psycho Fox if someone published a tool to edit the game content. also im not just porting psycho fox to the sega genesis/sega mega drive im all so porting it to the super famicom and the turbo grafix 16/pc engine

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