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vbSpec ZX Spectrum Emulator |
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|
vbSpec ZX Spectrum Emulator |
This site is sponsored by: |
Contributors
The following people have contributed towards the development of vbSpec:
Chris Cowley - Author and maintainer of
vbSpec. Head of Subtle Bug Development ("look, if I didn't put subtle bugs
in it, what incentive would there be for anyone to upgrade?")
vbSpec Version 1.6 Contributors
Mark Woodmass has
provided some performance-related enhancements and has also supplied an improved
routine for decoding port addresses (this basically means that vbSpec
v1.60 is more accurate and will work with more obscure and unusual demos and
games!).
He also assisted me in tracking down a problem
with loading certain TZX files and generally supplies help and moral
support by putting up with my long, rambling e-mails!
Gonchuki has
sent me many optimizations to vbSpec's core Z80 routines and display routines.
You have him to thank for a considerable portion of v1.60's improved
performance!
Ignacio Burgueno helped me with
a TZX compatibility problem. Ignacio is the author of Gleck, another fine Spectrum emulator for Windows.
Andrew Owen has kindly given permission for
his SE Basic ROM image to be distributed with vbSpec. More information about
SE Basic is available at The World of Spectrum Sinclair BASIC pages.
As always, the residents of the comp.sys.sinclair newsgroup and various other emulator authors have also been a great help.
vbSpec Version 1.50 Contributors
Mark Woodmass Mark (or
Woody, as he is more commonly known to the denizens of
comp.sys.sinclair) developed and submitted
the code for v1.50's TZX support, as well as tracking down and fixing a couple
of well-hidden bugs in vbSpec's Z80 core. For those of you not in the know,
Woody is also co-author of
SPIN, an
extremely accurate and complete Spectrum Emulator for Windows.
vbSpec Version 1.30 and 1.40 Contributors
Andrew
Owen Andrew provided the specification of the Timex TC2048 extended display
modes and timings, based on experimentation with his real TC2048. This
information is now available for other emulator authors in the
comp.sys.sinclair FAQ. He
also beta-tested the TC2048 support and provided various pieces of test code
that allowed me to get the TC2048 hi-res/hi-colour display modes working
properly. Andrew has also produced this slideshow
of hi-colour pictures to demonstrate the features of the TC2048.
Bob Woodring Supplied numerous
improvements and performance enhancements to the display code, based around
using pre-calculated lookup tables for various display-related calculations.
For the curious, his contributions are labelled 'RGW' in the source code.
Russell Marks Provided suggestions
for improving the accuracy of the AY sound in vbSpec by modifying the volume
table to more acurrately represent the measured voltages from a genuine 128K
Spectrum.
Many of the denizens of the
comp.sys.sinclair newsgroup, including Philip
Kendall and Mark
Woodmass, have also provided me with suggestions and invaluable assistance
about the finer points of the Spectrum hardware.
I would also like to thank the
numerous other people who have contributed ideas and source code for vbSpec. I
had no idea that the project would become as popular as it has, and I wasn't
expecting the volume of contributions that I've received! I may need to set up
a CVS tree for vbSpec in the near future as I currently have conflicting code
for a large number of new features. Working through these patches and additing
them to my primary copy of the source will take some time. However here are
some brief details of what I have yet to add:-
vbSpec Version 1.20 Contributors
James Bagg James is responsible for
adding the sound support to vbSpec 1.20. Not only did he do the majority of the
groundwork and research required to emulate the 48K Spectrum's beeper, he also
provided code for emulating the AY-3-8912 three channel sound of the 128K
Spectrum models. It was quite an experience for me to hear vbSpec producing
full 3 channel sound and effects for the first time -- he's done an excellent
job I think!
vbSpec Version 1.10 Contributors
Miguel Santos Miguel is the person
responsible for the substantial performance increase in v1.10. His tips
included replacing floating point division with integer division throughout the
Z80 emulation, replacing Iif() functions with block If's, and replacing various
occurences of integer and byte variables with longs. He also made various
helpful suggestions about improving the efficiency of the native VB display
routines. The end result is a version of vbSpec that runs around 2-3 times
faster than the previous release!
Sebastien Bauer Supplied patches to
enhance the keyboard routines with support for the PC backspace key and numeric
keypad.
David Bridson Sent some suggestions for
improving the display speed in vbSpec 1.00
