Hello
I would like to get to know the PCE architecture to start programming something in PCEASM.
Searching the internet, I did not find any satisfactory answers to my questions.
Therefore, I would like to know:
1. What is the best PCE emulator to test the written code and to have SPRITES or NAMETABLE view (unfortunately the ones I found don't have it).
2. From what I read, NAMETABLE in PCE has 1024 bytes ($ 000-03FF) of 32x32 size and one 8x8 tile address is supposed to have 2-bytes - not very correct because it should have 2048 bytes. It is very unclear:
https://www.chibiakumas.com/6502/pcengine.php"TileMap has to be at $0000 .. and it takes AT LEAST $0400 (it's minimum size is 32x32, and each definition takes 2 bytes)"
Due to this question, I do not know what the order of nametable tiles in PCE looks like - does it start like in NES (one-byte NAM)
xx00, xx01, xx02, xx03 ... xx1E, xx1F
xx20 ...
xx40 ...
(...)
Or like SMS (two-byte NAM)
xx00, xx02, xx04, xx06xx ... xx3E, xx3F
xx40 ...
xx80 ...
(...)
??
3. I have read PCE has the ability to access VRAM and VDP directly from the main processor loop without the need to perform additional graphics update functions, e.g. during VBLANK NMI? That's true? Are there maybe any limitations though? (For example, SegaMS can be written to VDP in the main loop (cpu loop) but you often have to make some delay between sequential writes due to slower transfer to VRAM.)
4. What exactly does a VRAM map look like? I found one but it is unclear - because if VRAM has 64K, why addresses from 8000 to FFFF are "unused"?
$0000 $03FF Min Tilemap (Tiles 0-63)
$0400 $0FFF Possible Tilemap (Tiles 64-255)
$1000 $7FFF Tiles 256-2048
$7F00 $7FFF SATB sprite table
$8000 $FFFF PC-Engine only has 64k, so this is unused
5. I couldn't find any good examples of HELLO WORLD in PCEASM - are there any? Correct reset code, joypad reading code, etc. Unfortunately, often different "hello world" have many errors and more confuse than advise.