Technical Resource Information

Techincal Resource Information
This "Technical Document" will give some idea on how the N64 runs. The text in normal font is basic emulation info, and the italic font is techi info. If this information helps you in any way, please e-mail me at, your opinions are as important as others. i've changed the layout, downloads are at the bottom while Basic info is at the top.

Basic Technical Information

R3400i: Found at the heart of the N64, the R3400i is the most valuable, yet most simple chip in the N64. This chip is required in order for the N64 to boot up, as well as for reading and writing to memory (without this chip, nothing would show). This chip is generally easy to emulate since it isn't too technical. Most authors use dynamic recompilation to speed up the process. Be sure you write the chip in Assembly, and remeber, 32-bit NOT 64-bit.

COP0: The COP0 has very many opcodes in it. The main object of this is for 'timing.' Many programs that use clocks require this chip. The Cop0 chip is essential for having color and pixels in your image. Cop0 also performs simple math calculations.

Cop 1 This chip is more on Virtual Memory. This is used to 'read' parts of the memory, in Project Unreality, you'll find lots of 'Unmapped Memory' problems. This isn't used by many ROMS but is a key role in emulating the N64.

COP2: COP2 should actually be called the RCP. The RCP is the key role to all the cool graphics and sounds on the N64. In order to emulate the RCP, you'll need good decoding skills and a FAST computer. The RCP has many opcodes, and is a pain in the bottom. This is a main obstacle for all emulation authors.
For your conveniece, I have included a whole bunch of RCP opcodes that are required for decent emulation of the RCP. This will be helpful to Emulation Authors:

2D Graphics: This just displays 2D screenshots. This can be used for ANIMATION too, if the screenshots made are in a certain order like animation cells for a cartoon. This is A MUST.

Controller: Duh. Why am I telling you about this?


Technical Documents:

N64 Toolkit Opcodes - 0.7 - A text file which has an extensive list of all the opcodes that need to be emulated as well as the functions of them. The list is currently incomplete.

R4300i microprocessor product information (HTML format) - A html file which displays  the functions of the R4300i chip, this file is about 700k.

R4300i Power Managment (Post Script Format) - Displays information about the power managment of the R4300i instruction set.

R4000 / R4400 User's Manual (PostScript Format) - the complete users/emulator authors/ guide to the R4000 /R4400 chip.

MIPS IV Instruction Set Revision 3.2 (PDF Format) - The name says it all.

V64 Mainboard - Information and pc's on the Doctor V64 mainboard with IC descriptions. Big file.

More tech downloads to come.


Last Updated: 10/03/98