Search found 116 matches

by cdoty
Sun Sep 23, 2007 5:14 pm
Forum: Megadrive/Genesis
Topic: asmx and padding?
Replies: 17
Views: 6266

My software doesn't pad anything, since erased (flash)EPROM already has FF in unused places... The padding could still be required, your eprom would be performing the 'padding'. What in the Genesis would require the padding? The checksum is software only. And would be affected by the padding only i...
by cdoty
Sun Sep 23, 2007 4:35 pm
Forum: Megadrive/Genesis
Topic: asmx and padding?
Replies: 17
Views: 6266

Yes, on real hardware... no problems... what flashcart you use ? maybe the problem lies in there... Yep, Probably the flash card. If you burn it to eproms, it's automatically padded out (and filled with 0xFF) by the eprom burning software. Or more accurately, eprom burning software is smart enough ...
by cdoty
Sun Sep 23, 2007 4:32 pm
Forum: Megadrive/Genesis
Topic: asmx and padding?
Replies: 17
Views: 6266

The genesis hardware need a 128 KB size alignment or your rom won't work correctly. You said objcopy do padding, can it does size alignement which is somewhat different from padding (padding just fill until you reach the pad size where alignement fill until size align). The NeoDev linker supports t...
by cdoty
Sat Sep 22, 2007 5:26 am
Forum: Megadrive/Genesis
Topic: asmx and padding?
Replies: 17
Views: 6266

My only use for the padding is MAME and MESS. MAME complains if the file isn't the right size (and about the checksum), and MESS refuses to run the Jaguar emulation if the file size isn't correct. Actually, another use is that the assembler should generate an error message if the file exceed the spe...
by cdoty
Thu Sep 20, 2007 5:43 am
Forum: Announcement
Topic: SuperH in the industry
Replies: 7
Views: 7250

There a lot of tools to develop for ARM without having to purchase any hardware: There's QEmu Arm (http://fabrice.bellard.free.fr/qemu/), skyeye (http://www.skyeye.org/index.shtml) and, the Rockbox simulator (http://www.rockbox.org/). There's also GBA and Nintendo DS. All of these support for GDB. T...
by cdoty
Thu Sep 20, 2007 5:32 am
Forum: Megadrive/Genesis
Topic: asmx and padding?
Replies: 17
Views: 6266

How about You don't use an "=" with org. Org is a directive, not a variable. You might want to do something more general - let's say we want to pad the rom to the next 128K boundary. Something like this: romEnd = (* + $1FFFF) / $20000 * $20000 org romEnd-1 ds 1,0 D'oh, where did the '=' came from? ...
by cdoty
Thu Sep 20, 2007 5:19 am
Forum: Hardware
Topic: My second cart board
Replies: 37
Views: 12742

8bitwizard wrote:And 65816 is semi-functional, in that it doesn't do some of the addressing mode force characters in the chip manual.
Is there a way to tell the assembler to use 8/16 bit values in 65816 mode?

ca65 uses .I8/.I16 and .A8/.A16, in addition to the REP/SEP instructions.
by cdoty
Thu Sep 20, 2007 3:54 am
Forum: Megadrive/Genesis
Topic: Hi - first post, with a whole bunch of questions...
Replies: 17
Views: 9951

This should be possible on a Genesis. You have to lay out the tiles so you can treat the display as a bitmap with a weird pixel layout. A lot of Mode 7 style games only have the lower 1/3 to 1/2 of the screen show the floor. The rest could be a scrolling tilemap. The rotation values are only calcula...
by cdoty
Thu Sep 20, 2007 3:31 am
Forum: Megadrive/Genesis
Topic: how gcc handle the stack to pass args to function
Replies: 3
Views: 2977

Yep. It's 4 bytes regardless of parameter size.

To align the code use:

.align x

where x is the byte to align to. For example, .align 4 creates DWORD alignment,
by cdoty
Wed Sep 19, 2007 6:56 pm
Forum: Video Display Processor
Topic: TV safe area
Replies: 123
Views: 44212

256x192 seems too much limited for safe area. When I worked in game company where we made games for NTSC TV console, we had safe area 288x216 and text safe area (where text is surely readible) 272x202 in 320x240 resolution on 14''..21'' CRT TV's. I think, I must check some games to get statistics, ...
by cdoty
Wed Sep 19, 2007 1:07 am
Forum: Megadrive/Genesis
Topic: asmx and padding?
Replies: 17
Views: 6266

Chilly Willy wrote:How about

Code: Select all

org 524287
ds 1,0
That's a beauty! Thanks.

It won't work with a defined value though:

Code: Select all

ROMSIZE = 524288

ORG = ROMSIZE-1
DS 1, 0
by cdoty
Tue Sep 18, 2007 9:39 pm
Forum: Megadrive/Genesis
Topic: asmx and padding?
Replies: 17
Views: 6266

asmx and padding?

Can padding be handled in asmx?

I tried:
ds 524288-*,0

But, this only works up to 1024 bytes, due to the MAX_BYTSTR define. Upping the size of the MAX_BYTSTR would work, but there has to be a cleaner way.
by cdoty
Tue Sep 18, 2007 4:17 pm
Forum: Video Display Processor
Topic: TV safe area
Replies: 123
Views: 44212

Here's the equivalent area for NTSC:

Image

This is based on:
http://www.interactivetvweb.org/tutoria ... sign.shtml

And agrees with 8bitwizard's 256x192 for anything important.
by cdoty
Mon Sep 03, 2007 6:12 am
Forum: SGDK
Topic: Sega Genesis Dev Kit (SGDK)
Replies: 765
Views: 282737

ElBarto wrote:Sweet.
I've started a template for visual studio 2005, will post it when it's finish.
Will it work on the Express version?

If so, may sure your keep it out of view from Microsoft, or you might get a cease-and-desist letter.
by cdoty
Mon Jul 09, 2007 3:33 pm
Forum: Tools
Topic: Echidna data linker
Replies: 1
Views: 2701

Echidna data linker

This isn't as useful for the Geneis, but could be useful for the Sega CD/32X, Saturn or, Dreamcast: Echidna data linker is a system of linking all of your files into one big file, that gets loaded from the CD. This should cut down on load times, as long as the file will fit in available memory. http...