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:
: http://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.
--
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
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:
: http://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.
--
All Comments