VDP speed curiousity

Page 5/12
1 | 2 | 3 | 4 | | 6 | 7 | 8 | 9 | 10

By hit9918

Prophet (2855)

hit9918's picture

16-02-2014, 22:38

@mars, the Panasonic MSX2+ doing E in Turbo mode.
If that was still in 60Hz, then it is a speed record. But it smells like the E of 50Hz machines.
When naming the machines, you should always mention the VDP hz, only then the spec is complete.

By Manuel

Ascended (15531)

Manuel's picture

16-02-2014, 22:39

Manuel wrote:

oh, good idea, R800 mode in openMSX:
220324
135344
4428
22705
13902
13841

Nowind working again (was my own fault), here's teh results on R800 on my own GT:
222366 (second run: 222105, third run: 222111)
136350 (second run: 136347, third run: 136355)
4430 (also second run and 3rd run)
22706 (also second run, third run: 22705)
13902 (second run: 13903, third run: 13902)
13853 (second run: 13852, third run 13853)

So, the first number has quite some variation and thus not very reliable as an emulator benchmark, at least. The 2nd number also has some variation, but it's a lot more stable. The other numbers only vary a tiny bit (1 in my runs). So they should be reliable.

Looks like openMSX fails mostly for the first two numbers, the rest is pretty good. (blueMSX seems to come with consistently too high numbers.)

Let's try for Z80 mode on my GT:
120149 (2nd run: 120212, 3rd run: also 120212)
77709 (also 2nd run, 3rd run: 77718)
6917 (also 2nd run, also 3rd run)
25011 (2nd run: 25009, 3rd run: also 25009)
18050 (also 2nd run, 3rd run: 18049)
8849 (also 2nd run and 3rd run)

Comparing with:

Quote:

on openMSX (FS-A1GT):
120140
77702
6916
25006
18048
8848

I'm pretty proud of openMSX here! Smile (And blueMSX too, it's practically the same.)

By mars2000you

Enlighted (5479)

mars2000you's picture

16-02-2014, 22:53

hit9918 : I use always the Auto Mode for the VDP frequency, so it was still 60 Hz, and I was even surprised by the result.

Btw, if you try 50 Hz on a Panasonic MSX2+, you get F in normal mode and you 'crash' immediately in turbo mode, without even reaching A !!!

By hit9918

Prophet (2855)

hit9918's picture

16-02-2014, 22:55

@mars,
I dont know, I just feel it sounds too good to be true Smile
It would mean the MSX2+ Turbo is 6/5 times faster in otir, accidentaly same ratio as pal vs ntsc timings,
that feels suspicious.
When on the real machine the display ratio is still same as always on 60Hz
(or TV can tell it is 60Hz) and you hit the E, then you got a winner.

By hit9918

Prophet (2855)

hit9918's picture

16-02-2014, 22:59

a crash? how does the crash look like? no red paint?

By mars2000you

Enlighted (5479)

mars2000you's picture

16-02-2014, 22:58

hit9918 : I think it needs to be checked on a real machine to be sure that something is not missing in the emulator.

By hit9918

Prophet (2855)

hit9918's picture

16-02-2014, 23:03

The code is so primitive, I got no idea in which way it would crash.
The letters on the low side is where a copy to vram starts. With otir.
On MSX1 there probably would be trashy wobbeling because of going too fast.
But normaly trash can happen only in vram contents, not on the cpu side.

By mars2000you

Enlighted (5479)

mars2000you's picture

16-02-2014, 23:06

hit9918 wrote:

a crash? how does the crash look like? no red paint?

By hit9918

Prophet (2855)

hit9918's picture

16-02-2014, 23:08

p.s. mhm it is in screen 0, there MSX1 can take the speed, too.

By hit9918

Prophet (2855)

hit9918's picture

16-02-2014, 23:08

@mars, that pic is no crash, it is a very fast machine Smile

Page 5/12
1 | 2 | 3 | 4 | | 6 | 7 | 8 | 9 | 10