Felix Posted September 5, 2012 Report Share Posted September 5, 2012 I know nothing about VGA, but had a question..On the Arcade and LogicStart boards,why are there only 2 resistors on the blue while there are 3 on the red and green? Link to comment Share on other sites More sharing options...
neslekkim Posted September 5, 2012 Report Share Posted September 5, 2012 3 bit of green, 3 bit of red, and 2 bit of blue.http://en.wikipedia.org/wiki/8-bit_color Link to comment Share on other sites More sharing options...
Pizus Posted September 5, 2012 Report Share Posted September 5, 2012 Hi,not sure but take a look at the source code vga_r <= vga_ram_data(7 downto 5); vga_g <= vga_ram_data(4 downto 2); vga_b <= vga_ram_data(1 downto 0);Maybe the Logicstart was tailored for the VGA driver.BTW the Arcade Megawing has 12b colours (4 resitors for each colour) Link to comment Share on other sites More sharing options...
Felix Posted September 5, 2012 Author Report Share Posted September 5, 2012 thanks i wonder if thats why my flatscreen tv doesnt like the papilio arcade.however, for the hardware thats being emulated it should be plenty, i guess. Link to comment Share on other sites More sharing options...
neslekkim Posted September 5, 2012 Report Share Posted September 5, 2012 I would check the frequencies, I would guess some tv's are a bit picky on those?I haven't tried mine on the tv yet, will be interresting to try. Link to comment Share on other sites More sharing options...
Felix Posted September 5, 2012 Author Report Share Posted September 5, 2012 You are probably right...iirc, most of the original arcade boards used 15Khz/60Hz...from the manual :Supported Display Resolution•Computer formatsResolution @ Refresh rate---------------------------------------640 x 480 @ 60Hz800 x 600 @ 60Hz1024 x 768 @ 60Hz1280 x 1024 @ 60Hz1360 x 768 @ 60Hz1600 x 1200 @ 60Hz1920 x 1080 @ 60HzI wonder if this is something that can be adjusted in the vhdl ?scan doubler? filesadly, @ work atm so can't even peek there. of course, who knows what else that would break. Link to comment Share on other sites More sharing options...
hamster Posted September 6, 2012 Report Share Posted September 6, 2012 As to why 2 bits for blue, but 3 for green and red... The eyes are more sensitive to red and green than blue, so an doubling the number of red and green levels vs blue gives best results.I've had Pacman running on a older 40" Sony V series, So it can't be that far off... Maybe run iSim and check the hSync frequency. Link to comment Share on other sites More sharing options...
Felix Posted September 6, 2012 Author Report Share Posted September 6, 2012 that makes total sense.i decided that i am not going to worry bout running the arcade stuff on the big tv since its all sideways anyways, and the wife would kill me if i turned the flatscreen on its side i will try with the A2601 stuff see if that shows up tho. Link to comment Share on other sites More sharing options...
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