Atarigmr

Great game, congratulations!

Understood. I did have BASIC on.

Thanx

It is working now after resetting the settings I wonder what was messing up things...

nope

It might be my settings then. I don't see any interlace and the lower part of the screen shows different.

I was looking at some pictures and this one(http://atari.fandal.cz/detail.php?files_id=5371) is not showing correctly. I am using Altirra 2.30 test 10

I have started to code it for a thomson machine I have created a blog for my retro codin' stuff but it is empty still.

It seems a good candidate for a port.

On their website you can load the games+sources. I have ported some of their games to the c64.

The Coco line of computers The Dragon 32/64 The French 8 bit computers from Thomson

Thank you for being so generous with your knowledge. Be sure I will bug you if I get stuck Today I spent sometime reading your tutorials here and other documents on the VDP. Then I copied your code(the randomize routines come specially handy I don't know if I am going to use them as they are but they are a starting point ) from this thread and adapted it to my needs. And at the moment I have graphics mode 2 working + sprites. Now it's time to get dirty with 'real' TMS9900 assembly as I need to start putting the game together(I am coding the same game on the 6502 and 6809, so I only need to translate what I already have and then add what else might be needed).

Awesome tutorials Matthew. Thanks.

Thanks Lee. Indeed it will be interesting coding for a processor without stack logic

Thank you guys, Yesterday I was reading 'beginning-assembly-language-for-the-ti-home-computer-second-edition' and it answered many questions I had about directives and 9900 asm Anyone know how the TMS7020 compares to the 9900? Ta.

Thank you

Hello Yesterday I have started to read about this machine, and I find that it is quite interesting. I am not acquainted with the TMS9900 processor but I am with the following ones: 6502, 6809, z80 and the 68000, from what I have read about the processor I don't think I will have major problems with it. I have downloaded the Asm994a Assembler (v. 3.009). I have typed and compiled a very simple test program, and then ran it with classic99 and it worked just as expected. At the moments I am reading about the VDP and the inner workings of the Ti-99/4a but I got worried when I came across in another thread where it was mentioned that there is a bug in this version of the assembler(instruction JMP?!), and it was mentioned also a patch but I couldn't download it, could someone send it to me(pvt me)? Also I couldn't find any documentation on this assembler, it would be nice to have it, in order to know what directives etc I can use. Are the existing emulators (Mess, classic99, and the simulator that comes with the assembler) reliable enough to be used for development/testing? Thanks

Very generous of you Bob. Thx.

@ Rybags thx for clarifying @PacManPlus Thanks, of course it had to be me doing something wrong, what I did in my haste to test transparency, I just put the high nibble to 0, which of course is wrong, I should have cleared bits 7,6,3 and 2 of the byte to have the first pixel transparent... dah Now, with a playing area so huge, I hope I will have enough cycles free for the game logic and music

BTW I have been doing gfx stuff by hand( not to bad because it was just for testing purposes and thus nothing complex) and also started to code a PC program to help with that but I'd rather not reinvent the wheel as time is something that we all lack - is there any programs to convert gfx from PC formats to a7800 format?

Thank you Rybags. Great to know about the wraparound at position 240, that'll solve things So MESS is not correct in showing only 226 line in PAL... I wonder about the transparency discrepancy I am getting on these emus.

I have been playing around with 7800 coding for sometime now... But I noticed that my program (testing mode 160x4) doesn't produce the same results in of two emulators I have tried it on, Prosystem and MESS. On Prosystem transparency is not working, the pixels show black, but on MESS they are transparent. I was thinking I would like to have sprites coming from outside the visible area (scrolling in), from the right side it is easy, but what about the left side as 0 is the first visible position, I thought of having a smaller visible area and cover the sides and then this would work but what if I want to use the whole visible area and have no black areas on the sides what would be the best approach? The program I am working on at the moment needs to display preferably 256 lines, but I can go with 240, is this possible?, thus I am aiming at the PAL A7800 (although I would prefer the NTSC palette). BUT this 240 lines show well on Prosystem emu but not on MESS as it only shows 226 lines (PAL) and when I tried the NTSC I noticed that it shows 225, which is odd, just one line more in PAL?! At the moment I have my dll, dl's and sprites and tiles all working but I am having this problems mentioned above and I will stop for now waiting for your insights on these issues as perhaps I am just wasting my time working with emus. (unfortunately I don't have the real hardware.) Thanks

Thank you EricBall.

What are the max displayable lines? Are they 240 like on the xl?

Thx Rybags, I have chosen char mode because I can have the 5th color. The 30 lines of the play area must be 8 pixels high each.