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Official spy hunter 5 website6/19/2023 ![]() ![]() show zc/to of channel 0 connected to clk/trg of channel 1. on a 2x2 grid (due to only 8bits for position data) - Z80-CTC : interruption ar managed by CTC chip. bytes #4 : not used - Athough 1x1 pixel defintion sprite position horizontal/vertical is made on Sprite data are organised (as seen by cpu F000-F1FF) into 128 * 4bytes. Thus cpu can read and update sprites position during entire frame except visible area and only by sprite machine during visible area. buffer is access by transfer address counter during 2 scanlines after buffer (512x8) is moved to actual sprite ram buffer (512x8). K6/L6) this buffer is read and write for cpu. Sprite data are stored first by cpu into a 'cache' buffer (staging ram at ram access is muliplexed between cpu and scanlines by using hcnt(0) in These accesses will create video artfacts aound mid display. In progessive mode there are video access around lines 240. In these areas cpu can access ram since scanlines are out of Real hardware uses background ram access after each 1/2 frame (~line 240 (look at 74ls86 G1 pin 9 on video genration board schematics) - *H and V stand for Horizontal en Vertical counter (Hcnt, Vcnt in VHDL code) - /!\ For VHDL port interlaced video mode is replaced with progressive video frame and 16 lines for even 2/2 frame thanks to V8 on sprite rom ROMAD2 Sprite are 32x32 pixels with 1x1 pixel definition, 16 lines for odd 1/2 background graphics is 2x2 pixels defintion. 31.75*525 = 16.67ms per frame (59.99Hz) - Original video is interlaced 240 display lines per 1/2 frame - H0 and V0 are not use for background => each bg tile is 16x16 pixel but Sprites ram : 512x8bits 512x8bits cache buffer - Sprites line buffer rams (graphics and colors) : 1 scan line delay flip/flop 2x256x8bits rbg programmable ram palette 64 (16 for sprites) colors 9bits : 3red 3green 3blue 4x32Kx8bits graphics rom 4bits/pixel single color set rbg programmable ram palette 64 (16 for background) colors 9bits : 3red 3green 3blue - 128 sprites, up to ~30/line, 32x32 with flip H/V 2x16Kx8bits graphics rom 4bits/pixel single color set 1x4Kx8bits graphics rom 2bits/pixel single hard wired color set - One scroling background tile map 16圆4 tile of 8x32 pixels One char tile map 30x32 tiles of 8x8 pixels ![]() sprite data ram, I/O, sound board register and trigger. (CRC list included) - Spy hunter (midway mcr) Hardware caracteristics : - VIDEO : CPU accessing its program rom, working ram, Use make_spyhunt_proms.bat to build vhd file from binaries Sound : OK - missing cheap/chip squeak deluxe board - Use with MAME roms from spyhunt.zip Video : VGA 31Khz/60Hz progressive and TV 15kHz interlaced Copyright (c) MikeJ - Jan 2005 - Educational use only gen_ram.vhd
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