Search found 22 matches

by charliegreen
Mon Jan 18, 2021 9:39 pm
Forum: Programming & Software
Topic: The Case of the Missing Cycles (Mode 41)
Replies: 7
Views: 2700

Re: The Case of the Missing Cycles (Mode 41)

There are only 224 scanline that the Uzebox draws. In fact you can set that to a lower number in most video modes with renderLinesCount and firstRenderLine. You could make the screen a bit more "letter box" by setting the renderlines to 186 and double the user CPU time. Oh, rad! I'm using mode 41, ...
by charliegreen
Thu Jan 14, 2021 8:48 pm
Forum: Programming & Software
Topic: The Case of the Missing Cycles (Mode 41)
Replies: 7
Views: 2700

Re: The Case of the Missing Cycles (Mode 41)

Ah, I see.. video rendering is more demanding than I remember. After refreshing my memory of NTSC, though, I'm a bit confused; I thought that 486 scanlines made the visible image, meaning 243 visible per field instead of 224? Also, looking at this timing diagram , each scanline is supposed to take 6...
by charliegreen
Wed Jan 13, 2021 10:27 pm
Forum: Programming & Software
Topic: The Case of the Missing Cycles (Mode 41)
Replies: 7
Views: 2700

The Case of the Missing Cycles (Mode 41)

Hello everyone! It's been a while! uzem says it's running at 30 MHz, and Wait100ns in uzeboxCore.c just runs the 3 cycle lpm instruction, which also suggests 30 MHz. At 60 fields per second, that suggests each field should have 500000 cycles available, right? Of course, much of that will be consumed...
by charliegreen
Fri Jan 05, 2018 10:37 pm
Forum: Programming & Software
Topic: New Video Mode: Mode 96
Replies: 9
Views: 4611

Re: New Video Mode: Mode 96

No, that define represents the cycle requirements of the inline mixer in that configuration, not how many cycles fit there. This just means that the inline mixer can not be used at all in that configuration with the current kernel. Oh, alright, cool. Thanks! I'll make my HSYNC_USABLE_CYCLES 230. Ot...
by charliegreen
Tue Jan 02, 2018 3:30 am
Forum: Programming & Software
Topic: New Video Mode: Mode 96
Replies: 9
Views: 4611

Re: New Video Mode: Mode 96

You're right, mode 41 doesn't use a huge amount more. And I didn't realize you could use multiple character sets at the same time, that's really cool! I'm trying it out for one of my games right now, and it's pretty nice! Excellent work :) A few minor suggestions, if I may (and let me know if I shou...
by charliegreen
Sun Dec 31, 2017 11:40 pm
Forum: Programming & Software
Topic: New Video Mode: Mode 96
Replies: 9
Views: 4611

Re: New Video Mode: Mode 96

Thanks! I hope it's useful! And oh wow, no, I didn't know about them. They seem pretty cool! They sure do use a lot of memory, though.... Maybe I'll try to make a "mode 42" that has 4-bit FG & BG attributes (unless someone else is already working on that?). I think mode 96 might still be better for ...
by charliegreen
Fri Dec 29, 2017 1:56 am
Forum: Programming & Software
Topic: New Video Mode: Mode 96
Replies: 9
Views: 4611

New Video Mode: Mode 96

Hello everyone! I've just written my first video mode, mode 96, and I want to share it with you all! It's a codetile-based mode with up to 256 6x8 1bpp tiles, where the color of each on-screen location can be set independently (eg, you can have two differently-colored 'A's on-screen at the same time...
by charliegreen
Wed Dec 13, 2017 3:55 am
Forum: Games & Demos
Topic: Snake
Replies: 12
Views: 6439

Re: Snake

Great, thanks!! I was just going to suggest you add it to the EEPROM reservation list, but it looks like you already did that! :)
by charliegreen
Mon Dec 11, 2017 3:28 am
Forum: Programming & Software
Topic: Accessing I/O space in avr-gdb; uzem bug?
Replies: 4
Views: 2325

Re: Accessing I/O space in avr-gdb; uzem bug?

Oh, cool, I hadn't! I had no idea CUzeBox had a feature like that! I'm still roughing out a lot of the logic of the video mode, though, so I'm sticking with uzem until I don't think gdb will be useful anymore, but that's good to know, and I'll probably use CUzeBox to finalize the timing. Does CUzeBo...
by charliegreen
Mon Dec 11, 2017 12:22 am
Forum: Programming & Software
Topic: Accessing I/O space in avr-gdb; uzem bug?
Replies: 4
Views: 2325

Accessing I/O space in avr-gdb; uzem bug?

Hello! I'm writing a video mode, and I'm not using AVRStudio for debugging, as I'm on Linux and AVRStudio is Windows-only. Right now I'm using uzem's gdb debugging mode and avr-gdb instead. I'm trying to read the TCNT1 I/O register to make sure my timing is right when emitting hsync pulses. I found ...