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Collection of Hack-Phreak Scene Programs
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cleanhpvac.zip
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NESA.ZIP
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NESA.DOC
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1996-10-11
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5KB
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132 lines
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N N EEEEEEE SSSSSSS AAAAAAAA
NN N E S A A
N N N E S A A
N N N EEEEEEE SSSSSSS AAAAAAAA
N N N E S A A
N NN E S A A
N N EEEEEEE SSSSSSS A A
Nintendo Entertainment System in Assembler
version 0.17 (Beta)
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IMPORTANT: This version of NESA uses a tweaked video mode which may not work
on all systems and could cause big problems with older cards & monitors.
Please feedback on how well this works.
Here is the latest beta version of my Nintendo NES Emulator for DOS. It is
written in assembler and is freeware. The only limitation is that it
must not be sold. I still retain copyright, of course.
It is 25k long and will run at a reasonable speed on most PCs. I have some
ideas for speeding it up a bit that aren't implemented yet.
Minimum required spec is probably 386SX-40/486SX-25,640k RAM,VGA
It supports Marat Fayzullin's NES cartridge format.
Image Types :-
Type 0 - most work (except for problems with 4017 writes !)
Type 1 - some work. Metroid seems ok but Zelda starts then dies !
Type 2 - Implemented. Seems to work ok.
Type 3 - VROM Switch (most of the larger PASOFAMI types) implemented ok.
(problems with some 8 x 16 sprites)
If a file won't work, check the following...
(1) The mirroring is correct. If its the wrong way round, some carts are
very wierd - lots of zeros,crashes etc.
(2) The file is ok. Try another copy - check the cartridge size is a
multiple of 8192 + 16
Command Line
============
nesa -h<n> -b<n> -e<n> -m<n> -s -t<n> -o<n> -q <cartridge>.nes
-h <n> Set # cycles for visible part of horizontal line (60)
-b <n> Set # cycles for vblank part of horizontal line (16)
-e <n> Set last scan line before VSYNC (256)
-m <n> Set redraw rate. Can now be any value (3)
-s Disable screen splitting. (off)
-t <n> Display next 200 scanlines from line <n>. Displays a 200 line
section of the screen,starting from scanline <n>. (off)
-o <n> Scroll override. You will notice that some screens are split in that
the score doesn't move when the game does - e.g. Mario. Try -o<n> if
the scrolling is in the wrong place where <n> is the scan line to
split .. 8-224 (off)
-q toggle cartridges stated mirror
These values can be changed if a game runs too slowly. Try setting -m7 first
then reducing h,b and e experimentally ! If these values are set too low then
some games will not work.
Keys
====
A Space
B Left Alt Key (or Z)
Select TAB
Start Enter
Move Arrow keys
Release 0.1 (Alpha) 10-Sep-96
First release.
Relese 0.11 (Beta) 11-Sep-96
Fixed bug - not updating z byte register correctly on PLP,RTI
Fixed bug - code in RAM didn't work,usually causing BRK.
Lots more games work now.
Runs a fair bit quicker.
Release 0.12 (Beta) 11-Sep-96
Implemented 8x16 sprites,not sure if they work !!!
Sprites behind background (Mario goes down pipes properly !)
Screen split code written. Partially works
Z as alternate key to Left Alt (Alt+Space in Win95,requested)
Start drawing from position rather than miss lines out (requested).
Supports multiple VROM Banks
Release 0.13 (Beta) 12-Sep-96
Supports SOME type 1 carts (very erratic !)
Supports type 2 carts (reasonably well)
Has battery backed RAM (which isn't yet,sorry)
Scroll line position override.
Release 0.15 (Beta) 30-Sep-96
Screen Skip Counter can be any value
Fixed sprite positioning problem (1 scan line down !)
Added support for the hit flag ?
Release 0.16 (Beta) 03-Oct-96
Fixed the palette.
Release 0.17 (Beta) 11-Oct-96
256x224 Screen.
Missing from this version .... :-
Player 2 Controls
Support for PC Joystick
Sound
Support for PAL Cartridges (anyone have any ?)
Backup the battery backed up memory.
Improve support for .NES type 1 carts
Thanks to :-
Marat Fayzullin for the NES architecture document on which this
emulator was largely based.
ChaosKnight and Robert Schmidt (tweak) for help with the
unusual video mode.
-------------------------------------------------------------------------------
Paul Robson
autismuk@aol.com