ARM - Revision history

Superogue at 19:12, 8 April 2024

2024-04-08T19:12:11Z

Superogue at 19:00, 8 April 2024

2024-04-08T19:00:48Z

Childishbeat: Childishbeat moved page ARM based CPUs to ARM: Less verbose

2022-04-08T15:41:45Z

Childishbeat moved page ARM based CPUs to ARM: Less verbose

Superogue at 12:56, 10 March 2022

2022-03-10T12:56:40Z

Superogue: Replaced content with "== Introduction == So here is a bit of help to get you started: === The ARM processor === The ARM Processor is a RISC based architecture and comes in many flavors."

2022-03-10T12:53:58Z

Replaced content with "== Introduction == So here is a bit of help to get you started: === The ARM processor === The ARM Processor is a RISC based architecture and comes in many flavors."

Tiririca: Added to ROM Header section

2020-09-10T14:37:28Z

Added to ROM Header section

Tiririca: /* = ROM Header */

2020-09-10T10:24:59Z

‎= ROM Header

Tiririca: GBA Rom Header explanation.

2020-09-10T10:24:39Z

GBA Rom Header explanation.

Superogue at 10:07, 10 September 2020

2020-09-10T10:07:46Z

Superogue at 09:42, 10 September 2020

2020-09-10T09:42:46Z

← Older revision		Revision as of 19:12, 8 April 2024
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	*'''[[Acorn Archimedes]]''' - Acorn Archimedes		*'''[[Acorn Archimedes]]''' - Acorn Archimedes
	*'''[[Gameboy Advance]]''' - Gameboy Advance Sizecoding Information		*'''[[Gameboy Advance]]''' - Gameboy Advance Sizecoding Information
		+
		+	== Generic ARM sinus table generator ==
		+	Here is a fairly generic ARM sinus table generator
		+	<syntaxhighlight lang="">
		+	To be added
		+	</syntaxhighlight>

← Older revision		Revision as of 19:00, 8 April 2024
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	*'''[[RISC OS on ARM based CPUs]]''' - Create your tiny intro on ARM hardware on RISC OS.		*'''[[RISC OS on ARM based CPUs]]''' - Create your tiny intro on ARM hardware on RISC OS.
		+	*'''[[Acorn Archimedes]]''' - Acorn Archimedes
	*'''[[Gameboy Advance]]''' - Gameboy Advance Sizecoding Information		*'''[[Gameboy Advance]]''' - Gameboy Advance Sizecoding Information

← Older revision		Revision as of 12:56, 10 March 2022
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	=== The ARM processor ===		=== The ARM processor ===
	The ARM Processor is a RISC based architecture and comes in many flavors.		The ARM Processor is a RISC based architecture and comes in many flavors.
		+
		+	*'''[[RISC OS on ARM based CPUs]]''' - Create your tiny intro on ARM hardware on RISC OS.
		+	*'''[[Gameboy Advance]]''' - Gameboy Advance Sizecoding Information

← Older revision		Revision as of 12:53, 10 March 2022
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	=== The ARM processor ===		=== The ARM processor ===
	The ARM Processor is a RISC based architecture and comes in many flavors.		The ARM Processor is a RISC based architecture and comes in many flavors.
−
−	~~== Gameboy Advance ==~~
−	~~The Gameboy Advance uses an ARM7TDMI Processor running at 16.7 MHz, 384kb of memory and a 240x160 pixel resolution.~~
−
−	~~=== Setting up ===~~
−	~~Setting up your development platform for the Gameboy Advance:~~
−
−	* Assembler: -
−	* Emulator(s): -
−
−	~~=== Video display ===~~
−	~~The Gameboy Advance has many graphics modes to play in both 256 colors as well as 15-bit direct RGB access, as well as support for tilemaps and 128 hardware sprites with a max 64x64 resolution.~~
−
−	~~==== Getting something on screen ====~~
−	~~To be added soon.~~
−
−
−	~~=== Sound ===~~
−	~~The Gameboy Advance has 4 channel sound + 2 x DMA for digital audio.~~
−
−	~~==== Make some noise ====~~
−	~~To be added soon.~~
−
−	~~=== ROM Header ===~~
−	The Gameboy Advance ROM header is 192 bytes in size, where 156 bytes are reserved for the Nintendo logo. The first 4 bytes in the ROM header is a ARM-branch instruction to the actual code. The following 156 bytes are the mandatory Nintendo Logo. At offset 0x00A0 the header expects a game title in maximum 12 bytes. These 12 bytes can be reused by inserting instructions instead of a game title. Following the game title, the next 4 bytes are the game code, which can also be used for instructions. After the game code, 2 bytes for the maker code are reserved, which can be used, when already changed into THUMB-Mode. The next byte is fixed and has to be always 0x96. The next byte is free, but hardly to make usage of. One could try to create a useful instruction using the byte before or in general here could be stored some value. After this, another 8 bytes can be used for instructions from offset 0x00B4. At offset 0x00BD a complementary check for the header has to be calculated. If the calculated checksum is different than the stored value, the ROM won't boot. Since some values in the header are fixed, which normaly should be jumped over, one can analyse the resulting instructions created by that fixed bytes and decide whether just slide through it.
−
−	~~=== Additional Resources ===~~
−	* [https://problemkaputt.de/gbatek.htm GBATEK]
−	* [https://www.pouet.net/prodlist.php?type%5B%5D=256b&platform%5B%5D=Gameboy+Advance Pouet: 256 byte productions for the GBA]

@@ Line 28: / Line 28: @@
 === ROM Header ===
-The Gameboy Advance ROM header is 192 bytes in size, where 156 bytes are reserved for the Nintendo logo. The first 4 bytes in the ROM header is a ARM-branch instruction to the actual code. The following 156 bytes are the mandatory Nintendo Logo. At offset 0x00A0 the header expects a game title in maximum 12 bytes. These 12 bytes can be reused by inserting instructions instead of a game title. Following the game title, the next 4 bytes are the game code, which can also be used for instructions. After the game code, 2 bytes for the maker code are reserved, which can be used, when already changed into THUMB-Mode. The next byte is fixed and has to be always 0x96. After the fixed byte, another 8 bytes can be used for instructions from offset 0x00B4. At offset 0x00BD a complementary check for the header has to be calculated. If the calculated checksum is different than the stored value, the ROM won't boot.
+The Gameboy Advance ROM header is 192 bytes in size, where 156 bytes are reserved for the Nintendo logo. The first 4 bytes in the ROM header is a ARM-branch instruction to the actual code. The following 156 bytes are the mandatory Nintendo Logo. At offset 0x00A0 the header expects a game title in maximum 12 bytes. These 12 bytes can be reused by inserting instructions instead of a game title. Following the game title, the next 4 bytes are the game code, which can also be used for instructions. After the game code, 2 bytes for the maker code are reserved, which can be used, when already changed into THUMB-Mode. The next byte is fixed and has to be always 0x96. The next byte is free, but hardly to make usage of. One could try to create a useful instruction using the byte before or in general here could be stored some value. After this, another 8 bytes can be used for instructions from offset 0x00B4. At offset 0x00BD a complementary check for the header has to be calculated. If the calculated checksum is different than the stored value, the ROM won't boot. Since some values in the header are fixed, which normaly should be jumped over, one can analyse the resulting instructions created by that fixed bytes and decide whether just slide through it.
 === Additional Resources ===
 * [https://problemkaputt.de/gbatek.htm GBATEK]
 * [https://www.pouet.net/prodlist.php?type%5B%5D=256b&platform%5B%5D=Gameboy+Advance Pouet: 256 byte productions for the GBA]

← Older revision	Revision as of 15:41, 8 April 2022
(No difference)

@@ Line 27: / Line 27: @@
 To be added soon.
-==== ROM Header ===
+=== ROM Header ===
 The Gameboy Advance ROM header is 192 bytes in size, where 156 bytes are reserved for the Nintendo logo. The first 4 bytes in the ROM header is a ARM-branch instruction to the actual code. The following 156 bytes are the mandatory Nintendo Logo. At offset 0x00A0 the header expects a game title in maximum 12 bytes. These 12 bytes can be reused by inserting instructions instead of a game title. Following the game title, the next 4 bytes are the game code, which can also be used for instructions. After the game code, 2 bytes for the maker code are reserved, which can be used, when already changed into THUMB-Mode. The next byte is fixed and has to be always 0x96. After the fixed byte, another 8 bytes can be used for instructions from offset 0x00B4. At offset 0x00BD a complementary check for the header has to be calculated. If the calculated checksum is different than the stored value, the ROM won't boot.

← Older revision		Revision as of 10:07, 10 September 2020
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	=== Additional Resources ===		=== Additional Resources ===
	* [https://problemkaputt.de/gbatek.htm GBATEK]		* [https://problemkaputt.de/gbatek.htm GBATEK]
		+	* [https://www.pouet.net/prodlist.php?type%5B%5D=256b&platform%5B%5D=Gameboy+Advance Pouet: 256 byte productions for the GBA]

← Older revision		Revision as of 09:42, 10 September 2020
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	=== Additional Resources ===		=== Additional Resources ===
−	* ~~links to be added~~	+	* [https://problemkaputt.de/gbatek.htm GBATEK]