2011.02.17 Thanks te_lanus for submitting news Today I’ve gave a look at the Sony SMC-777 HW again. The system uses a “ timed” bankswitch, presumably involving instruction pre-fetching. For example (this is BIOS ROM code, located at 0×0000-0x3fff): 3BF3: 3E 10 ld a,$10 3BF5: D3 1C out ($1C),a ;enables RAM bankswitch 3BF7: C7 rst $00 ;executes this, then switches to RAM mode Enabling this and adding the unimplemented features makes all of the available programs / games to boot properly with sketchy keyboard and some games with imperfect colors (presumably missing clut): http://mamedev.emulab.it/kale/wp-content/uploads/2011/02/0133.png http://mamedev.emulab.it/kale/wp-content/uploads/2011/02/0147.png http://mamedev.emulab.it/kale/wp-content/uploads/2011/02/0146.png http://mamedev.emulab.it/kale/wp-content/uploads/2011/02/0142.png http://mamedev.emulab.it/kale/wp-content/uploads/2011/02/0143.png http://mamedev.emulab.it/kale/wp-content/uploads/2011/02/0144.png http://mamedev.emulab.it/kale/wp-content/uploads/2011/02/0149.png http://mamedev.emulab.it/kale/wp-content/uploads/2011/02/0139.png http://mamedev.emulab.it/kale/wp-content/uploads/2011/02/0137.png http://mamedev.emulab.it/kale/wp-content/uploads/2011/02/0150.png http://mamedev.emulab.it/kale/wp-content/uploads/2011/02/0151.png http://mamedev.emulab.it/kale/wp-content/uploads/2011/02/0152.png http://mamedev.emulab.it/kale/wp-content/uploads/2011/02/0153.png ______________________________________________________________________________ 來源：http://mamedev.emulab.it/kale/?p=1365 ※ 引述《conpo (びんぼうがみ)》之銘言： : 2011.02.13 : Take the Red pill : Fixed address readback in rf5c68 and added a preliminary audio redbook : support in Mega CD / Sega CD driver … results are shown in this YT video: : https://www.youtube.com/watch?v=xqZKrv9Yo7E&feature=player_embedded : ______________________________________________________________________________ : 來源：http://mamedev.emulab.it/kale/?p=1360 : ※ 引述《choan (八房龍之助)》之銘言： : : http://mamedev.emulab.it/kale/ : : Fixed a timing GD-ROM DMA bug to not fire the irq and zero the status flag : : instantly. This allows us to boot The King of Fighters Neowave. --

※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 59.115.177.101 ※ 編輯: conpo 來自: 59.115.177.101 (02/17 13:49)