Changes

FPGAmstrad

105 bytes added, 17:42, 9 January 2018
/* VGA */
=== VGA ===
Pixels and VRAM. Palette and rasters. CRTC0
==== VGA: CRTC0 ====
CRTC0 seems the best one, some demo does cry when detecting a poor CRTC1 (CRTC1 seem a low cost version of CRTC0). I have to implement a CRTC0 instead of my current CRTC1...
In ZX-Uno FPGAmstrad, I implemented CRTC0.
==== VGA: TODO : arnoldemu testbench - crtctest ===='''arnoldemu testbench: crtctest''' 
Adding choice of CRTC 0 or 1 on OSD, and passing this test could be great.
==== ram_palette VGA: TODO : winape testbench ===='''winape testbench: plustest''' a better border heuristic Using winape testbench (plustest), test 2 does show somes problems while border does go out of screen, negative border does hide line itself. ==== VGA: VRAM ====ram_palette. 
VRAM contains 800x300 amstrad pixels (VZoom x2), displayed VGA 800x600@72Hz with fix regular border at 768×576 and fix inside border at 768×544.
RAM_palette contains the ink list and the mode for each line of VRAM, sampled at horizontal middle of 800x600 screen, and used at begin of each line.
 
==== TODO : a better border heuristic ====
Using winape testbench (plustest), test 2 does show somes problems while border does go out of screen, negative border does hide line itself.
=== bootloader ===
1,200
edits