nesdev.org

They all fetch bg tiles during active display and fetch sprite patterns during H-blank. Hi, i havent found that in the TMS9918A/TMS9928A/TMS9929A Video DisplayProcessors pdf, in it explains only about Vblank, there are no references to Hblank, or retrace period, about Hblank is explained in the gen...

Part of the memory map is a direct fixed mapping from virtual addresses to physical addresses, with granularity of 512 MiB. (The entire virtual memory range from 0x8000_0000 through 0x9FFF_FFFF, as it says on the wiki, directly addresses physical memory from 0x0000_0000 through 0x1FFF_FFFF. I under...

The N64 has an MMU with TLB, yes, but it also has an MMU bypass. Reportedly most games use the bypass, because there's not much advantage when it's a single-user single-process system that's usually cooperatively threaded. More detail I have read that the only addresses that the cpu handles are vir...

I made a mistake, since the debugging process control the registers so control the program flow, I was writing about that when I wrote about mmap I believed that N64 only handled virtual memory, you say that is it possible to access the RAM directly?, can you access all the registers of the processo...

There was no 100% standard way to operate the DMA unit or the joypad ports in software. All of that was up to the developer. You could learn by identifying code in commercial games that touches the relevant registers, or you could just study how the registers work and write your own. (Actually, if ...

It's not just DMA. The way the PPU of machines like the SNES and the NES work, indexing into graphics as counted per tile (usually 8x8 pixels) is hardware supported, whereas reading/writing individual pixels must be done in software by the CPU (and as such, manipulation of graphics on a sub-tile/pe...

I would like to understand what you say, but it is too sophisticated for me, I know that vblank is part of the kernels in other consoles, I think I understand that you would use dma to transfer a tile, dma uses block transfers, I think that's why you say it is not convenient to write only one pixel ...

You'd have to establish the context first. Since the SNES has no text mode, you'd need to supply typeface graphics as part of your program, load them into VRAM, and set up the display to use them. Once you've done that, it's possible to write text to a tilemap in order to display it. Right 93143, t...

I have not been able to do it yet, I'm working from laevateinn, to see how every part of the snes hardware works as a whole,
there must be a way to imitate printf

Many things are the ones that I have to study in order to program a snes game, I know I do not know the native language aka 65816 assembly as to communicate directly with the devices, with respect to the memory system, I understand that apple 2 GS provides APIs for communicate and read / write in me...

totally agree, that way it is possible to make programs in c, the ORCA / C compiler for apple 2 allows to make programs that fit apple memory system and it/s peripherals, the way to compile for the snes memory system is not equal but similar, plus other devices

Tepples, what you told me about the invocations of functions, has to do with that, when I received the indefinite references to functions, they were indefinite references within libraries, not inside headers, for example "undefined symbol _printf" as an error message, where _printf is invo...

The way it's supposed to happen, as I understand it, is that a hosted implementation of the C language comes with a C standard library implementation whose printf calls fputc(codeunit, stdout); or fputs(stdout, codeunits); or fwrite(codeunits, 1, num_codeunits, stdout); . It expects the underlying ...

CPU is one thing, but you have all the non CPU bits like the sound and video side and compiler is completely oblivious to those. You'd have to write your own stdio and other libraries to get going (which is essentially what everyone has to do to anyway when they start doing retro game dev). That is...

There are no threads. There is no OS. There is no kernel. There is no "joystick interrupt". Welcome to working on actual bare metal. From this paragraph, it's fairly obvious you need to start by learning about general CPU architecture and assembly language (65xxx is fine, but the concept ...