Business with the Z80
Monday, 12th December 2005
I have been pretty busy with Brass and Latenite over the last few days - Latenite has had a few little adjustments/improvements/fixes, but also has a few new holes in it which means that it is unsuitable for release. I'm adding the ability to hook help files to projects rather than each project being loaded with every help file - this has the extra bonus that Brass will be able to compile help files straight from the source, which will then be reloaded on each build by Latenite.
I did something unheard of over the weekend as well - I read the SDK manual for the TI-83 Plus. Mainly because I was trying to work out how some of the function calls worked, but also the stuff they talk about with regards to applications (as opposed to programs - applications fill multiple 16KB pages of ROM on the calculator, programs are variable sizes and are copied to RAM location $9D93 for execution) was pretty interesting - and it sounds pretty nightmarish! I'll download some of the application development tools, see if I can puzzle them out and then try and recreate their behaviour in Brass. It's yet another output format - Brass can, with the .binarymode directive, switch between a number of binary output formats, including TI calculator formats (TI-73, TI-82, TI-83, TI-83+, TI-85, TI-86), raw binary and a number of hex text files (Intel, Intel word address, MOS technology and Motorola).
I'd never really understood how the LCD display driver worked on the TI-83 Plus, and the SDK documentation was pretty useful - even though I still can't quite work out why the X axis goes from top-to-bottom and the Y axis goes from left-to-right. It turns out direct access to the LCD can produce some very fast results... (and the world's worst greyscale):
Download binaries for TI-83/TI-83 Plus [Ion/MirageOS]
Yes, yes, I have a little 'something' about 3D tunnels.
It lives!
Monday, 5th December 2005
A public release of Brass has been released... it can assemble some rather nasty Z80 code (TASM macro-abusing code, that is!) fine. Hopefully people can start finding the parse errors, or just complain at the horrible colour scheme of the manual.
And why did nobody tell me you could access the LSB/MSB of IX/IY through IXL/IXH/IYL/IYH before?
@kwijibo: You can use a Latenite beta if you take this file then unzip this file on top of it. It is almost entirely data driven - all Z80 registers (that I knew about) and flags (likewise) are hard-coded (but not Z80 instructions).
BRASS
Wednesday, 30th November 2005
One logical step up for Latenite is to not have to be bundled with a 3rd party assembler.
Mainly because one (high profile!) user is having real problems getting the buggy TASM to work with it, and other people have expressed annoyance with TASM, (limited string length, limited label length, limited numbers of DBs, lack of features, buffer overflow crashes... the usual) I have decided that I need to write an assembler (BRASS).
WLA-DX is very nice but is geared towards console development and burning programs on ROMs, and defining a ROM bank map for a TI-83 Plus program is a bit silly. I will try and keep it as compatible with TASM as possible, so old TASM-geared code still compiles, but will add some new features.
(BRASS at the top, TASM at the bottom - not that it actually matters!)
A lot of work still needs to be done - supporting ZIDX/ZIX/ZBIT instructions (anything like BIT *,A or LD A,(IX*)) is a pretty important one, for starters. The expression parser (for things like "_label+21" needs to actually parse expressions (all it does at the moment is check for and substitute in labels or numbers). Directives for conditionals and macros (and macros themselves!) need to be worked in.
Currently supported directives: .org, .include (#include maps to .include), .locallabelchar and .module.
.include could do with some work, this will compile (or rather, it won't ever get into pass 2):
File: test.asm
.include "test.asm"
I also need ideas for directives. Some are already in my mind (.dbsin, .include_once (like PHP's require_once()), .incbin)... What would you implement if you were writing a Z80 assembler?
I hate syntax highlighting.
Monday, 28th November 2005
I spent this weekend completely rewriting the syntax highlighting control - this time, from scratch. It seems that all the free ones are rubbish. 
Mine is rubbish, but at least I can maintain it. 
Now all I have to do is wait for the people using the beta to start complaining that it's eating their source code...
My test project for it was a Lotus-like 3D racing engine.
I think I need to research the way it works a little better... still, not too bad for a little over 400 bytes.
Themes!
Wednesday, 23rd November 2005
Not the www2 theme though - a couple of XP theme glitches.
First up is the ListView control in .NET 2. If you switch on gridlines and scroll with the arrows on the scrollbar, it leaves the gridlines behind as nasty artefacts. This is what I came up with - and it appears to work.
Create a new class that inherits from ListView. Then add to it this code:
/// <summary>
/// Hacky override to fix the garbage lines.
/// </summary>
protected override void WndProc(ref Message m) {
if (m.Msg == 0xF) { // 0xF is WM_PAINT
GridLines = false;
GridLines = true;
}
base.WndProc(ref m);
}
...compile and that new class should appear in your toolbox. Use that instead of the normal ListView control.
If anyone could come up with a better solution, I'd love to hear it...
The other theme bug appeared last night in XP.
I guess it can't remember if it's using Windows Classic or Windows XP styling?