sz81 Code

188 lines (126 with data), 7.0 kB

* Changes between versions   -*- mode:indented-text; mode:outline-minor -*-

This file (NEWS) documents the significant changes between all
versions of z81, with the newest changes first.


* Changes in z81 2.1

Fixed several compilation warnings with gcc, as well as something gcc
now likes to call an "error" which prevented compilation of z81 2.0
with current versions. Thanks to Adam J. Richter and Brian Schau for
pointing out the problems.

Added a "saverom" program for the ZX81, which lets you save your
own ZX81's ROM.

Changed ZX80 VSYNC behaviour slightly, the Space Invaders clone for it
works now.

Various sound fixes - fixed post-death sound in QS Defender, fixed a
slight `spike' problem on VSYNC tones, and removed AY tone/noise
counter wraparound (which was mistaken).

Improved signal handling.


* Changes in z81 2.0

Better display emulation, leading to better emulation all-round. This
still isn't perfect, but it already seems to cope with everything z81
1.x did, plus a bit more. Notable additions are Rock Crush, Dan's
Revenge, and QS Defender (though it's so overscanned it doesn't fit in
the normal display). Also, high-score entry now works in ZX Galaxians,
and the display no longer `goes weird' when updating on the ZX80. :-)
Thanks to Wilf Rigter (and his zx81vid.txt) for the timing info and
detailed description the new display stuff was based on.

Optional sound emulation. This comes in two forms - VSYNC-based (aka
`turn up the volume on the TV' :-)), and AY-3-891x-based (sound
addons). The sound addons currently supported are the Quicksilva sound
board, and the Bi-Pak Zon X-81 (thanks to Andy Styles for info on
this). The sound code was based on my work for Fuse, so Matan Ziv-Av
and Philip Kendall also deserve some credit here.

Added ZX Printer support, which was an easy port from xz80. Thanks to
Ian Collier for this, obviously. :-) The main difference in z81 is
that it outputs (as a picture) to a PBM file rather than an X bitmap.

With `-l', you can now boot directly to the file selector (at least
when emulating a 16k ZX81).

You can now enable display of the VSYNC signal with `-V'. This is
useful if you want FAST mode to blank the screen, or want to see
LOAD/SAVE signals onscreen when using `-L' or `-S' (see below), but
tends to be an annoyance otherwise which is why it's not enabled by
default.

The LOAD and SAVE hooks can now be disabled, with `-L' and `-S'
respectively. This is mainly so there's something easy to get at which
makes a noise :-) (i.e. use `-sS' then save something).

A keyboard port fix means that Namtir Raiders now works. Also fixed
reversed key-reading when more than one bit was zero in the port's
MSB - I don't think that affected much though.

You can now directly emulate a 1k machine, with `-u' (= unexpanded).

The new `-i' option inverts the screen, giving a white-on-black
display.

Fixed some problems with signal blocking when exiting.

The X version previously ignored any `-r' setting - fixed.

Auto-load (loading from the command-line) is slightly better
than before - it now starts up the program `instantly'. This is
probably just as well, as the better display emulation means the
emulator can't really `fast-boot' any more except when loading a
program.

It didn't previously load programs from command-line which ended in
`.P' (it tried to add a further `.p') - it does now.

Removed the old `-s' for normal (slow) booting, as the only fast-boot
option now available is auto-loading (see above).

Removed z81txt (the Linux-console-specific text version). I thought
about some way of making it work with the new display code by
interpreting characters in the screen bitmap, but it was really just
too nasty an idea to be worth bothering with.


* Changes in z81 1.3.1

Incredibly moronic bug fixed - it seems that in 1.3, I managed to
completely break all loading and saving *except* LOAD "".

Now uses SA_RESETHAND if SA_ONESHOT isn't available, which should
avoid a compilation problem on Solaris. Thanks to Philip Kendall for
pointing this out.


* Changes in z81 1.3

Fixed several possible buffer overruns.

The LOAD "" file selector now allows simple directory navigation, and
shift-q/shift-a to page up/down in the file list.

A few changes to avoid possible problems with copyright etc. - in
particular, the ROMs are no longer included.

Added support in X version for `delete window' message from window
manager.

Fixed the old bug where the X version wasn't redrawing in some
circumstances. This was due to Expose events on the image window not
being propagated to the parent (the slightly larger `borderwin').

The default SCALE (as specified in the Makefile) is now 2, giving a
more reasonable window size for the X version.

Added uninstall target to Makefile.

z81txt is no longer built by default.


* Changes in z81 1.2

Added `zx81get', a (Linux-specific) program to read ZX81 tapes using a
soundcard (or more precisely, using /dev/dsp :-)).

Fixed xz81's 1-bit mono support to work on X servers with `LSBFirst'
bit order. Thanks to Christopher Allen for pointing me in the right
direction on this one.

Fixed auto-load bug (for programs loaded from the command-line), where
most programs which didn't just do an immediate USR after loading
acted oddly or simply crashed.


* Changes in z81 1.1

xz81 should support pretty much all display depths now. At any rate,
it works for me at 1/8/15/16/24/32 bpp; 4-bit should work, but is
currently untested.

There's an important bugfix relating to glibc - previously it wouldn't
have compiled!

There are a few bugfixes in the emulation, meaning that a couple of
games which didn't work before (e.g. Artic's "ZX Galaxians") do now.
Thanks to Claudio Carlquist for pointing out one of these bugs.

Z81 now uses svgalib's raw keyboard support rather than rawkey.

I'm including yet another naff ZX81 PD game I wrote :-) - `mine81', a
minesweeper clone.


* Changes in z81 1.0

ZX80 support.

When emulating a ZX81, you get a file selector if you do LOAD "" (in
all versions).

Help screen supported in X version (8-bit displays only, as yet).

Uglier but more readable (and thus more useful) hand-hacked help
screen. (This also has the advantage of being B&W, so I don't have to
worry about allocating colours in xz81 - which I would otherwise have
had to do *just* for the help screen!)

The ZX81 now boots instantly, by using a snapshot of a booted machine.
Use `-s' if you don't want this to happen for some reason.

Removed misguided top-speed and extremely-low-refresh-rate options.
You can achieve the same effect as the latter by starting with `z81 -r
25' or similar. Anyone who used the top-speed feature probably used it
for entering programs - using FAST mode is good for this.

ANSIfied the code and cleaned up almost all the code duplicated
between versions.

Data files are now installed in /usr/local/lib/z81 by default. Also,
xz81.xpm and zx81sml.gif are installed there (they weren't before).