Search found 72 matches

by hstubbs3
Thu Apr 25, 2024 3:53 pm
Forum: Works In-Progress Discussion
Topic: Some things I've been working on
Replies: 16
Views: 810

Re: Some things I've been working on

Is kinda funny was thinking about like 'Another world' sorta stuff as I was getting to work this morning and.. if you are already doubling pixels.. one could just scale the screen to be say 160x200 ... that would give enough leeway to use _sprites_ instead of bitmap layers to cover the screen - you ...
by hstubbs3
Wed Apr 24, 2024 12:22 am
Forum: Works In-Progress Discussion
Topic: Some things I've been working on
Replies: 16
Views: 810

Re: Some things I've been working on

At the moment you can see there are several issues. But it's working. It's about 0.5 frames per second. The game uses "dirty buffering" combined with double buffering. The double buffering is slow because no DMA. The dirty buffering will be quite fast once I have optimised the polygon fil...
by hstubbs3
Wed Apr 24, 2024 12:13 am
Forum: Works In-Progress Discussion
Topic: Some things I've been working on
Replies: 16
Views: 810

Re: Some things I've been working on

The reason the pic drawing is so fast is because it's using assembly. I had to learn about the bresenham algorithm and span filling flood fill. One of the bonus things about the 4-bit mode is that one byte represents 2 pixels, which is the same as the EGA mode on MS-DOS. So you can read and write p...
by hstubbs3
Thu Apr 11, 2024 5:49 pm
Forum: CX16 General Chat
Topic: How to Use VERA FX "Line Helper"?
Replies: 15
Views: 804

Re: How to Use VERA FX "Line Helper"?

LDA #magic_enable_8bit LDX #magic_enable_4bit loop: STA FX_CTRL ;4, Disable FX 4-bit BIT DATA0 ;4, Read DATA0 but don't store it in A BIT DATA0 ;4 BIT DATA0 ;4 BIT DATA0 ;4 STX FX_CTRL ;4, Enable FX 4-bit STZ DATA1 ;4, Write cache to VRAM with 4-bit transparency ; = 28 cycles This will save 4 cycle...
by hstubbs3
Wed Apr 10, 2024 8:18 pm
Forum: CX16 General Chat
Topic: How to Use VERA FX "Line Helper"?
Replies: 15
Views: 804

Re: How to Use VERA FX "Line Helper"?

According to Verilog , FX docs : When using the 32-bit cache... If FX 4-Bit Mode is ON, Transparent Writes mode will function on each zero- nybble of the 32-bit cache when you attempt to write the cache to VRAM. If FX 4-Bit Mode is OFF, Transparent Writes mode will function on each zero- byte of th...
by hstubbs3
Wed Apr 10, 2024 6:26 pm
Forum: CX16 General Chat
Topic: How to Use VERA FX "Line Helper"?
Replies: 15
Views: 804

Re: How to Use VERA FX "Line Helper"?

The FX routines also pay no attention to the target being 4bit or 8bit... which could be fun, as using 4bit mode with BYTE increments against an 8bit target could allow you to overwrite either nibble, possibly just switching palette offset of the pixel, maybe with a given palette that means could l...
by hstubbs3
Wed Apr 10, 2024 3:46 pm
Forum: CX16 General Chat
Topic: How to Use VERA FX "Line Helper"?
Replies: 15
Views: 804

Re: How to Use VERA FX "Line Helper"?

I wonder if after that, the last thing is this - /* Occasionally increment by 1 */ VERA_ADDRx_H = 0x10; but.. you want occasionally increment by 1 _nibble_ ... VERA_ADDRx_H = 0x14; the auto-increment doesn't automatically factor in the FX being in 4bit... The FX routines also pay no attention to the...
by hstubbs3
Tue Apr 09, 2024 11:21 pm
Forum: Programming
Topic: Memory Banking Question
Replies: 18
Views: 669

Re: Memory Banking Question

How many Rom an benches are there in the x16? What are they called please? Where can you find the sys commands for the rom commands? Thanks. Those are not published APIs, so the address for those can change between builds. If you want to inspect the code to see how it works, you can check out the R...
by hstubbs3
Tue Apr 09, 2024 11:21 pm
Forum: Programming
Topic: Memory Banking Question
Replies: 18
Views: 669

Re: Memory Banking Question

It doesn't list the addresses to JSR to for the BASIC commands .. poking around the ROM repo, I think I understand why that is ... https://github.com/X16Community/x16-rom/blob/master/basic/basic.s https://github.com/X16Community/x16-rom/blob/master/basic/tokens.s The way the ROM is currently assembl...
by hstubbs3
Tue Apr 09, 2024 8:26 pm
Forum: Programming
Topic: Memory Banking Question
Replies: 18
Views: 669

Re: Memory Banking Question

hello, thanks for help. which rom number is the basic rom in x16 ? Is there a complete rom listing for this please? I only see excerpts in the x16 doc. greeting. BASIC interpreter is in bank 4. If you mean basic as in "essential" then it would be ROM bank 0, as you would set ROM bank 0 be...