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Posted: Sat Feb 16, 2013 3:35 pm
by zhengyaxin_8bit
Posted: Sat Feb 16, 2013 4:11 pm
by zhengyaxin_8bit
I still have some questions did not find out
Code: Select all
NMI: MOVEM.L d0-a7,-(sp)
CMP.W #$ff,m_IRQFlag
BNE ?OnlyMusic
MOVE.W #$8A30,$C00004 ;Set the interval
MOVE.W #$8014,$C00004 ;Enable IRQ
Code: Select all
IRQ:
MOVEM.L d0-a7,-(sp)
MOVE.W #$8A01,$C00004 ;Set new irq Cycle
I set twice interval in NMI(Vint) and IRQ(Hint),The settings in IRQ do not take effect immediately.
Code: Select all
NMI #$8A30--->$C00004
......
NMIEND
......
SOME TIME
IRQ #$8A01--->$C00004 ;here changes Interval =0x01
......
IRQEND
Interval--0x30 ;why wait 0x30? I think that will wait 0x01
IRQ1 #$8A01--->$C00004
......
IRQ1END
Interval--0x01
IRQ2
......
NextNMIBegin
Posted: Sat Feb 16, 2013 4:29 pm
by zhengyaxin_8bit
[/img]
Note the white spots on the left,It represents the start of the Hinterrupt.
Posted: Sat Feb 16, 2013 5:05 pm
by TmEE co.(TM)
Interrupt count is only updated when interrupt happens, not when the count register is written to.
Posted: Mon Feb 25, 2013 1:42 am
by greatkreator
zhengyaxin, are you aware that it doesn't work on the real device?
just black screen.
Posted: Mon Feb 25, 2013 2:30 am
by zhengyaxin_8bit
greatkreator wrote:zhengyaxin, are you aware that it doesn't work on the real device?
just black screen.
I have confirmed that it is good on the real device。These pictures from the interception on the hardware
Posted: Mon Feb 25, 2013 2:38 am
by greatkreator
I tested it on sega genesis 1 and have seen a black screen on my tv.
Did anyone else execute it?
by the way can you use PM on this forum? I have sent you message concerning help in my project.
Posted: Mon Feb 25, 2013 6:24 am
by zhengyaxin_8bit
greatkreator wrote:I tested it on sega genesis 1 and have seen a black screen on my tv.
Did anyone else execute it?
by the way can you use PM on this forum? I have sent you message concerning help in my project.
Hardware platform may vary。Which country you are?I calculate the time difference
Posted: Mon Feb 25, 2013 10:39 am
by greatkreator
ntsc sega genesis 1
i am in Ukraine now
Posted: Mon Feb 25, 2013 10:48 am
by TmEE co.(TM)
That screenshot is from real hardware, in 50Hz and at 240 line resolution. This does not work in 60Hz.
Posted: Mon Feb 25, 2013 11:19 am
by greatkreator
what is reason it doesn't work in 60 hz?
Posted: Mon Feb 25, 2013 12:19 pm
by TmEE co.(TM)
240 line mode is not supported in 60Hz, the VDP will not generate VBlank and VBL interrupt runs in 30Hz. Horizontal ints probably don't work because of it...
Posted: Mon Feb 25, 2013 12:26 pm
by greatkreator
sadly.
too much restrictions and limitations in the palette switching.
another one confirmation that that is a niche for demos.
sadly.
i have wasted quite a lot time to make it useful in a real project
but not successfully.
by the way TmEE do you know any sega games except Toy Story that used it?
Posted: Mon Feb 25, 2013 3:52 pm
by zhengyaxin_8bit
greatkreator wrote:what is reason it doesn't work in 60 hz?
It can work in NTSC and PAL.But the HINT time is shorter in NTSC. if you want to get the better effect,we need to adjust the code. For example,
Code: Select all
MOVE.W #0x8A02, 0xC00004 ;0x8A01-->0x8A02
or Upgrade cpu speed of operation. My cpu(TCT6803) allows such
Code: Select all
move.w #0x00f7,0xA1630C |set to NTSC
CheckROMInfo:
move.w #0x5350,0xa14480 |raise cpu speed, 0xffff to close,0x5350 for raise
move.w #0xBf,0xa14484 |Double cpu speed
Posted: Mon Feb 25, 2013 3:58 pm
by greatkreator
can you please build ntsc build?
sadly i cannot do it currently.
thank you.