Nintendo Entertainment System

The Nintendo Entertainment System or NES, was Nintendo's 8 bit console in the battle against Sega's Master System during the late 80s and early 90s. Technically inferior to the SMS, but sporting the trademark characters of the Super Mario Brothers, long before Sonic was even a twinkle in daddy hedgehog's eye, the NES dominated America's home video game market. It was never quite as successful in Europe, where Sega seemed to be well dug in, yet the NES still made it into many British homes. Nevertheless, what the NES lacked in technical capabilities, it made up for in playability with Zelda and Mario even spawning sequels on the N64 today.

The NES had a strange system of mappers that were used to set up how the ROM was to be accessed. There are many different mappers for different games (nearly 100 at last count), and each one needs to be coded separately in an emulator, so it is important that you check whether the emulators on the Acorn can run each game so beware of this in case your favourite game doesn't work.

MadNES

Having decided to ditch ARCNes, mainly due to a lack of feedback from users and a lack of time, David McEwen has ported MadNES. He had initially tried to get the source to RockNES, but after a lack of response from the team, he decided to look elsewhere. So he turned to MadNES, an upcoming NES emulator by Roberto Rosario. Due to David's knowledge of the system gleaned from doing ARCNes and a decent amount of info on the net he has been able to give Acorn users some benefits over the PC version, even though he hasn't got the latest source. The most notable is the ability to run Elite, although at this stage the emulation is far from perfect. MadNES is a growing into a very complete emulator with sound support, although not present in the port at this time, and lightgun emulation. NES emulators have to be very accurate to get certain games to run and the accuracy of MadNES can be seen by it's attempts to run various games by RARE, which are notoriously difficult to emulate. The PC version is currently a later one than the port and as such we can expect much improved compatibility and quality in the next release, combined with support for compressed ROMS.

MadNES 0.10 (10/01/99)
Speed Rating: ARM 3 ARM 6 ARM 7 StrongARM

David McEwen's homepage with MadNES to download
MadNES homepage

ArcNES

David McEwen has been manged to port xNES the NES emulator by Michel David and Richard Hamel (amongst others) to the Acorn. xNES was previously developed by a team of people, who suddenly dropped it leaving their latest version unreleased, after an argument over copyright theft (which was largely unsubstantiated). As a result of this, further versions from the team are very unlikely. The emulator was left at quite an early stage, although most of the main code was there and it could run most games, and the team released the source code to the public. David has been busy doing some upgrades to the emulator himself, speeding up wasteful routines and adding to the many mappers in the emulator which allows more games to run, and seems to be improving the compatibility all the time. Since the emulator has been changed so much from its origins, it has now been renamed ArcNES. Since then, new programmers have adopted the old xNES code and are continuing it for the PC, under the name RockNES.

Since the emulator is written in C (allowing the port) the emulator is not desperately fast, but can still run on pre-RISC PC machines, although you really need something a lot faster. The compatibility can be something of a problem at the moment, with several mappers unsupported, though it has to be said, it's a lot better than many PC NES emulators. The sprite priority is not quite perfected yet, but although it looks a bit strnage when Mario descends outside the pipe, it's not a major problem. The ArcNES archive contains a list of buggy games in the !Help file, so I suggest you read that before you download any games that don't work. ArcNES has now been discontinued in favour of MadNES.

ArcNES v0.60 (28/8/98)
Speed Rating: ARM 3 ARM 600 StrongARM

ArcNES (31Kb ZIP file)
Generic xNES page at emulation camp
xNES source code

M.E.S.S.

Since the xNES source code had been made freely available, it also occurred to others to continue work on it. Brad Oliver continued to develop it, and changed it into a driver for MESS. Many more mappers have been added to it to much improve the level of compatibility, and interestingly different mappers have been added to the MESS driver and David's port making them subtley different. MESS NES also has preliminary sound emulation, although it's not perfect yet. The speed is not as good as David McEwen's port of the last release of xNES, probably as a result of the underoptimised system and the necessity for compatibility with the other drivers, but the game compatibility is a lot better with even the notoriously tricky to emulate NES elite running quite successfully. This apparently runs upto 25fps on a StrongARM, and sometimes more depending on the settings.

Speed Rating: ARM 3 ARM 600 StrongARM

MESS

Neditor

NES images contain a header before the actual data copied off the cartridge, which tells the emulator important information about the hardware the game expects to find. For various reasons, ROM image headers can be easily corrupted (sometimes on purpose) and need fixing using a ROM image header editor, such as Neditor, by David Sharp (myself). This can solve many problems with ROM images which won't run under NES emulators without being 'cleaned'. If you use a NES emulator I suggest you use Neditor.

Neditor v1.02 (23/8/98)

Technical Information
CPU - NMOS 6502 running at 1.7897725MHz
Display- 256x240 pixels, 64 sprites at once, 26 from a palette of 52 colours
Sound - 4 channels + digital sound channel
RAM - 8Kb with infamous MMCs to get past the 16bit (64Kb) program counter boundary
VRAM - 8Kb
ROM - upto 512Kb
reference - NES documentation by Y0SHi (Jeremy Chadwick) revision 1.00

NES world - loads of background info on the NES

ROMs:
NES ROMs
Ultimate NES emulation
Underground Cities NES roms
Duoduo - NES ROMs in packs
EmU EvIsCeRaTiOn
Hacked NES ROMs
Silver1979s ROMs
ROM World
Elite World NES ROMs
SOMulation NES ROMs
Nintendo 8bit power

Recommended ROMs:
Super Mario Bros. 1 and 2 (3 doesn't work), Zelda, Bomberman, Elite (one of the best versions), Megaman, Contra, Teenage Mutant Ninja Turtles.