ChangeLog.z81

2004-10-01  Russell Marks  <russell.marks@ntlworld.com>

	* Version 2.1.

	* z81.1: added a more practical `best' emulation example, and
	trimmed down see-also section.

	* Added current version of tetris1k (with lines-cleared display),
	and matching source in tetris1k-src-newer.tar.gz. Also moved the
	games/demos to a new `games-etc' dir.

2004-09-17  Russell Marks  <russell.marks@ntlworld.com>

	* zx81get.c: was missing #include <stdlib.h>. Thanks to Brian
	Schau for spotting this.

2001-11-03  Russell Marks  <russell.marks@ntlworld.com>

	* sound.c (sound_ay_overlay): envelope now applied when period is
	zero. Fixes post-death sound in QS Defender.

2001-10-16  Russell Marks  <russell.marks@ntlworld.com>

	* sound.c (sound_beeper): fix for slight `spike' problem on VSYNC
	tones.

2001-10-15  Russell Marks  <russell.marks@ntlworld.com>

	* sound.c (sound_ay_overlay): removed tone/noise counter
	wraparound (which was mistaken).

2001-09-27  Russell Marks  <russell.marks@ntlworld.com>

	* Signal handler called on `bad' signals no longer tries to
	immediately exit (which is potentially a bad idea), but merely
	sets a flag so we can deal with it next time we would
	ordinarily draw the screen and so on.

	* common.c (usage_help): removed embedded LFs from string.

2001-08-12  Russell Marks  <russell.marks@ntlworld.com>

	* saverom/README: after a successful test of saverom with my ZX81,
	tweaked a few things here slightly (having two `lines' of the
	listing end with "LN 2 graphs7" was confusing, for example).

2001-08-06  Russell Marks  <russell.marks@ntlworld.com>

	* common.c (out): it looks like OUTs to FEh should turn off VSYNC
	on ZX80. With this fix, the ZX80 space-invaders clone works.

	* README: changed to say that only the ZX81 ROM is really required
	before you can run z81. Bit of a simplification, but better than
	saying you need both (which was never true).

	* Added `saverom' dir, containing a program to save the ROM from a
	ZX81, for loading via zx81get.

2001-08-02  Russell Marks  <russell.marks@ntlworld.com>

	* z80.h: `interrupted' isn't volatile these days. Thanks to Adam
	again.

2001-07-31  Russell Marks  <russell.marks@ntlworld.com>

	* z80.c: needed #include <string.h> to avoid warnings (though
	curiously, I didn't get any on gcc 2.95.2). Thanks to Adam J.
	Richter for spotting this.

2001-07-27  Russell Marks  <russell.marks@ntlworld.com>

	* Version 2.0.

2001-06-26  Russell Marks  <russell.marks@ntlworld.com>

	* common.c (startsigsandtimer): fixed some signal-handling
	problems; all `bad' signals which are handled are now blocked
	while in the handler (via sigaction()'s sa_mask), and any planned
	exit now works by raising a signal so that our signal-blocking
	happens for that too.

2001-06-23  Russell Marks  <russell.marks@ntlworld.com>

	* New `GAMENOTES' file covering problems you might have loading
	certain games (or more commonly, certain modified versions of
	them).

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

2001-06-21  Russell Marks  <russell.marks@ntlworld.com>

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

	* Added aydemo.p (along with source), intended as a demo of the
	various AY-based addons. Currently only works with the Zon X, but
	that should change in time. The tune is a port of my ingame music
	for `zblast'. :-)

2001-06-20  Russell Marks  <russell.marks@ntlworld.com>

	* common.c (parseoptions): added option for ACB stereo. It's not
	generally much use on the '81, but again, I had the code just
	sitting there... :-) You add an `s' suffix to the AY board type,
	e.g. `-a qs'.

	* common.c: the LOAD "" file selector is no longer optional. There
	was never much point in having that option anyway.

	* Added Bi-Pak Zon X-81 sound addon support. Thanks to Andy
	Styles for providing the necessary details to add this.

	* common.c: you can now boot directly to the file selector (at
	least when emulating a 16k ZX81), with `-l'. Aborting (with Space)
	currently aborts the emulator, which is arguably inconsistent
	given what the normal autoload does on error, but I think is
	probably what you'd want.

2001-06-18  Russell Marks  <russell.marks@ntlworld.com>

	* sound.c: added support for AY-3-8910/8912-based sound chip
	addons. Hey, I'd already written the AY code, so why not? :-)
	Currently supports Quicksilva's one (start with `-a q' to enable
	it), which gives effects in their Asteroids, Invaders and Defender
	games. (The effects in Defender are quite good, BTW...) The clock
	speed is currently a guesstimate, until I can find some
	documentation.

	* common.c (initmem): ok, it looks like an unexpanded ZX80 has 1k,
	not 4. :-)

	* When using `-V', you now get a visual indication of (busy) FAST
	mode as you might expect; the screen turns black. My previous
	non-synced display wasn't triggered when always in VSYNC, as it is
	when grinding away in FAST mode.

	* You can now enable display of the VSYNC signal with `-V'. This
	is nice if you want to see LOAD/SAVE signals onscreen when using
	LOAD/SAVE and `-L' or `-S', but it can be an annoyance when typing
	in programs, as you get the line-entry flicker the ZX81 used to
	have, which the default frameskip makes particularly off-putting
	since it'll only be shown half the time...!

	* common.c: you can now disable the LOAD and SAVE hooks, 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), though you don't get the matching display yet.

	* Added sound support (ouch). Only for OSS (e.g. Linux) I'm
	afraid. It's based on VSYNC, which I think is probably how sound
	was usually produced. The code is based on my sound code for Fuse,
	so Matan Ziv-Av deserves a large slice of credit for fixing many
	problems with the original implementation :-), and the code would
	never have been written in the first place without Philip
	Kendall's emulator.

	* common.c (printer_inout): fixed slight bug in the printer
	support; previously, the first pixel line of a character was
	shifted right one pixel, which was visible on block graphics and
	inverse text.

2001-06-17  Russell Marks  <russell.marks@ntlworld.com>

	* z81.1: made option listing consistently bold, not a bold/italic
	mix. This is a bad habit exhibited in a lot of my old man pages,
	and I've got to start fixing them somewhen - this may as well be
	the first. :-)

	* Added printer support, very directly ported from xz80, so thanks
	are entirely due to Ian Collier for this. Again. :-) The main
	difference in z81 is that it outputs (as a picture) to a PBM file
	rather than an X bitmap; they're even simpler, take less space,
	and everything reads them. The printer support is *normally
	disabled*, but you can enable it by running with `-p foo.pbm',
	where foo.pbm is the file to direct any printout to. Note that
	even when printing is disabled, the emulation goes through the
	motions; this e.g. stops COPY from hanging the machine, as it
	would otherwise.

	* common.c (load_selector): wait for them to let go of all keys
	before starting. Needed particularly for the 1k ZX81, as that
	responds rather more quickly to LOAD "" than the 16k...
	(in): now resets bit 7 of input port FEh, which fixes Namtir
	Raiders. Also fixed reversed key-reading when more than one
	bit was zero in the port's MSB.

	* xmain.c: got rid of the rrshm vs. rrnoshm thing - most will be
	using shared memory, and you'll probably have to drop the frame
	rate a *lot* for non-local use (it only halved it). So it's best
	to just stick to a 25fps default in all cases. Which has the added
	advantage of matching the documented behaviour. :-)

2001-06-16  Russell Marks  <russell.marks@ntlworld.com>

	* common.c (parseoptions): ok, formalised that - removed `-s'
	option for normal (slow) booting, as it always does that now
	except when auto-loading.

	* z80.c (mainloop): auto-load works again, and is actually better
	than before - it starts up the program `instantly'. This is
	probably just as well, as I don't think I'll be re-enabling
	fast-boot apart from that (loading a program is a nice clean point
	to hook into without video-related hassles, but such opportunities
	are pretty rare).

	* z81txt removed. I thought about some way of making it work by
	interpreting characters in the screen bitmap, but it was really
	just too nasty an idea to be worth bothering with.

2001-06-15  Russell Marks  <russell.marks@ntlworld.com>

	* You can now emulate a 1k ZX81, with `-u' (= unexpanded). (With
	`-o', this emulates a 4k ZX80, which I think was the unexpanded
	RAM size...?)

	* xmain.c (main): X version previously ignored any `-r' setting,
	fixed that. Also removed some unnecessary code.

	* common.c (load_selector): selector works again.

	* Massive reworking of display code and lots of related stuff.
	It now works by actually emulating the workings of the display
	(rather than just having the emulator look at D_FILE and draw
	it), avoiding a lot of unsightly kludges previously needed in
	order to get the thing running. This fixes a few things
	relative to the previous behaviour - Rock Crush and Dan's
	Revenge now work, high-score entry in ZX Galaxians works, the
	ZX80 display no longer `goes weird' when updating :-), QS
	Defender works better than it did before (but the screen is
	strangely placed, etc.), the ZX81 emulation speed is more
	accurate. The changes have left a few things broken for now -
	the file selector, snapshot-based fast booting on the ZX81,
	and auto-load. Oh, and the ZX80 screen is offset to the right
	for some reason.

2001-05-13  Russell Marks  <russell.marks@ntlworld.com>

	* Version 1.3.1.

	* common.c (load_p): incredibly moronic bug fixed - it seems I
	managed to completely break all loading and saving *except* LOAD
	"". Conclusive proof that I can type in my sleep, I guess. :-/
	It's been a long time since I last did an x.y.1 release of
	anything, but I think this is bad enough to call for it...

2001-05-11  Russell Marks  <russell.marks@ntlworld.com>

	* common.c (startsigsandtimer): 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.

2001-03-21  Russell Marks  <russell.marks@ntlworld.com>

	* Version 1.3.

	* The ROMs are no longer included, as the legal situation seems
	more uncertain than I'd previously thought. (This change was
	actually made a few weeks ago, but I forgot to mention it here.)

2001-03-02  Russell Marks  <russell.marks@ntlworld.com>

	* common.c (libdir): fixed several possible buffer overruns.
	Package maintainers doing an audit are advised to do more than
	just grep for strcpy/strcat etc. ;-), as I've not just used
	snprintf() everywhere...
	(load_selector): selector now supports shift-q and shift-a (from
	the ZX81's perspective, so Alt/Meta also works) for paging up and
	down in the file list.

	* Makefile: added uninstall target, and removed z81txt from
	default (`all') target such that you have to explicitly choose to
	make it.

2001-02-19  Russell Marks  <russell.marks@ntlworld.com>

	* Removed zx81*.gif and zx81.cdr.gz. While I drew this myself, it
	could easily be seen as infringing on Sinclair's keyboard design,
	since it was obviously intended to be a close match. Better not to
	risk it, I think. I'd hope zx8[01]kybd.pbm are ok, as these are
	more like abstracted diagrams than close copies.

2000-12-16  Russell Marks  <russell.marks@ntlworld.com>

	* common.c (do_interrupt): avoid gcc `ambiguous else' warning.
	(load_selector): selector now allows simple directory navigation.

1999-07-19  Russell Marks  <rus@cartman>

	* Makefile: z81 doesn't use vgagl, so don't link it! Also, removed
	WHITE_ON_BLACK def for z81txt; that should really apply to all
	versions or none, and shouldn't be a compile-time option even
	then.

1999-06-17  Russell Marks  <rus@cartman>

	* xmain.c: added support for `delete window' message from window
	manager. (The code is pinched from dosemu, which in turn pinched
	it from xloadimage. :-))

1999-06-15  Russell Marks  <rus@cartman>

	* xmain.c: fixed the old bug where the X version wasn't redrawing.
	This was due to Expose events on the image window not being
	propagated to the parent (the slightly larger `borderwin').

1999-06-12  Russell Marks  <rus@cartman>

	* Makefile: changed default SCALE to 2. I didn't quite have the
	guts to do this until getting a faster machine myself (i.e. one
	which can cope with it), but now I have I can see how much more
	sensible a default it is. :-)

1999-05-29  Russell Marks  <rus@lifeson>

	* common.c: gave IMC credit in usage message.

1999-05-11  Russell Marks  <rus@lifeson>

	* Version 1.2.

	* z81.1: reformatted synopsis to avoid horrible line-break.

1999-04-26  Russell Marks  <rus@lifeson>

	* common.c: fixed auto-load bug, where most programs which didn't
	just do an immediate USR after loading acted oddly or simply
	crashed. The way I've avoided this is to reimplement the auto-load
	in a slightly more BFI manner, by automatically `typing' a LOAD
	command. :-)

	* common.c: massively sped up checking for hi-res screen. Unlikely
	to be noticeable in practice, though. :-)

1999-04-24  Russell Marks  <rus@lifeson>

	* README: various corrections and clarifications.

	* Added `zx81get', which loads ZX81 programs via /dev/dsp
	(presumably from tape). It's not perfect, but it's worked
	pretty well for me - I've managed to get a couple of really
	horrible-sounding recordings to load successfully. However,
	it's Linux-specific (AFAIK) and needs a sound device which can
	record in 22kHz 8-bit mono.

1999-04-17  Russell Marks  <rus@lifeson>

	* xmain.c: fixed 1-bit mono support to work on servers with
	`LSBFirst' bit order. Thanks to Christopher Allen for pointing me
	in the right direction on this one.

1999-03-11  Russell Marks  <rus@lifeson>

	* Version 1.1.

	* Updated tetris-src etc. so it refers to my hacked copy of zmac
	rather than relying on a patch to the old comp.sources.unix one.
	Also added mine81, another PD ZX81 program I wrote a while back.

1999-02-28  Russell Marks  <rus@lifeson>

	* common.c: no longer assumes struct sigaction's sa_mask can be
	zeroed with a simple `=0' (this fix was needed for glibc).

1998-11-03  Russell Marks  <rus@lifeson>

	* common.c: made reading from keyboard port work if more than one
	bit of a8..a15 is zeroed, which mostly fixes "ZX Galaxians" (but
	see TODO).

	* z80.c: now sets top bit of R on reset. Thanks to Claudio
	Carlquist for finding this bug.

1998-10-16  Russell Marks  <rus@lifeson>

	* xmain.c: now supports every bit depth I could test - in all
	that's 1-bit, 4, 8, 15, 16, 24, and 32. The way it does it is
	impressively stupid :-), but it should at least work.

1998-10-15  Russell Marks  <rus@lifeson>

	* Made Z81 use svgalib's raw keyboard support. Unfortunately,
	Z81txt still has to use the rawkey stuff, so I put that in
	txtrawkey.c.

Tue Sep  1 12:09:17 1998  Russell Marks  <rus@lifeson>

	* common.c: if Esc was pressed when file selector was being used,
	it effectively locked up. Fixed that by ignoring Esc when in file
	selector (which seems the most sensible thing to do).

Mon Mar 30 20:31:29 1998  Russell Marks  <rus@lifeson>

	* Version 1.0.

	* common.c: added file selector. It works via the ZX81's screen,
 	and so works on all three versions.

	* The ZX81 now boots instantly, by using a snapshot of a
 	booted machine. Use `-s' for the old behaviour.

Thu Mar 12 19:36:39 1998  Russell Marks  <rus@lifeson>

	* commonraw.c: fixed sneaky little bug introduced in the recent
	code reorganisation which meant that the `z' key didn't work.

	* Finished off ZX80 support.

Wed Feb 18 03:16:46 1998  Russell Marks  <rus@lifeson>

	* Added support for starting a .P file from the cmdline.

Tue Feb 17 21:33:01 1998  Russell Marks  <rus@lifeson>

	* Started adding ZX80 support. Haven't got the rom yet, so there
	are limits to how much I can do, but... :-)

Tue Feb 10 04:49:36 1998  Russell Marks  <rus@lifeson>

	* Fairly major reorganisation of the code, ANSIfying it and moving
 	out previously duplicated bits (where possible) to common*.c. Also
	removed the rather pointless top-speed and low-rate toggles in
	Z81/Z81txt.

	* xmain.c: added support for help screen.

	* main.c: switched to an uglier but more readable hand-hacked help
 	screen (zx81kybd.pbm) which I should be able to also use in the X
	version.

	* xmain.c: partially `fixed' problem with opaque movement under X;
 	at least now it redraws after the movement has finished.

Tue Feb  3 04:21:44 1998  Russell Marks  <rus@lifeson>

	* Makefile: moved default position for rom etc. to
	/usr/local/lib/z81. The idea behind having it in /usr/local/lib
	was that other emulators could share the rom, but in practice I
	doubt there are going to be too many other Unix-based ZX81
	emulators. :-) (Besides, it's only 8k, so having unnecessary
	copies wouldn't be a big deal.)

Sat Jan 11 04:06:46 1997  Russell Marks  <rus@lifeson>

	* Version 0.2.

	* Added 1k tetris.

Thu Oct 17 16:23:06 1996  Russell Marks  <rus@lifeson>

	* Added zx81{sml,big}.gif and zx81.cdr.gz.

Sun Oct 13 03:55:05 1996  Russell Marks  <rus@lifeson>

	* main.c: made similar change. No point doing it for txtmain.c,
	that's so fast already it'd probably just make it slower.

	* xmain.c: speeded up screen refresh hugely, by following xz80's
	lead and updating differentially. This is a real pain given the
	ZX81's screen, and a fair bit of BFI is required to implement it,
	but it's *so* much faster.

Sat Oct 12 01:27:07 1996  Russell Marks  <rus@lifeson>

	* Made detection of end of `booting' a lot more sensible.

	* Updated z81/z81txt to use sigaction rather than signal.

	* xmain.c: (and others) quick hack to support reset. Fairly
	painful, but it works well enough.

Fri Oct 11 16:33:53 1996  Russell Marks  <rus@lifeson>

	* xmain.c: created, after semi-infinite amounts of hacking. :-) An
	X version (finally).

Fri May 10 02:21:09 1996  Russell Marks  <rus@lifeson>

	* Added rather kludgey but working PAUSE support.

Sat Apr  6 20:25:29 1996  Russell Marks  <rus@lifeson>

	* Fixed keyboard hardware emulation - top 3 bits were 0 before
	(now are all 1). "3D Grand Prix" didn't work before due to this
	bug. And does now. :-)

	* Added maximum-speed and low-refresh-rate toggles on F9 and F8
	respectively.

Sat Apr  6 04:38:42 1996  Russell Marks  <rus@lifeson>

	* main.c: added help screen with ZX81 keyboard layout.

Wed Apr  3 02:05:46 1996  Russell Marks  <rus@lifeson>

	* main.c: added high-res support.

Mon Mar 25 04:32:28 1996  Russell Marks  <rus@lifeson>

	* txtmain.c: fixed screen updating here, too.

	* main.c: fixed screen updating so it works properly with less
	than 32x24.

	* z81.1: added.

	* main.c: made it read rom from /usr/local/lib.

Tue Sep 26 17:59:21 1995  Russell Marks  <rus@lifeson>

	* New text-mode variant, 'z81txt'. Still requires a console, but 
	will work on MDA/CGA/EGA displays (as well as VGA, though 'z81' is
	preferable in that case).

Mon Aug 28 20:40:48 1995  Russell Marks  <rus@lifeson>

	* Version 0.1.