Questions about cycles \ VOGONS

Questions about cycles

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First post, by Excalibur

Posted on 2011-02-10, 23:08

Excalibur Offline

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Joined: 2011-02-10, 22:56

Hello

I have a few questions about the concept of "cycles" in dosbox which I wasn't able to resolve with the help of the available documentation and hope to find some answers here.

1) Is a cycle an absolute or a relative unit, meaning is a game running at fixed number of cycles A exactly as fast on a Pentium IV as on the latest Heptacore from AMD?

2) Are there any charts that show which number of cycles corresponds approximately to which kind of computer? I mean something like X cycles = 286 with 16 MHZ, Y cycles = 486 with 33 MHZ etc.

3) How can I find out which is the maximum amount of cycles my computer can process? What happens if I keep increasing the maximum number of cycles with CTRL-F12 and step over this limit?

Bye

Reply 1 of 5, by leileilol

Posted on 2011-02-10, 23:53

leileilol Offline

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1) Absolute IIRC

2) No and that's just wrong because it's nothing more than fuzzy approximates.

3) You'll get slow motion with choppy sound (A TOOL ASSISTED PLAYER'S DREAM THROUGH HARD DIFFICULT GAMES TO MASSAGE THEIR INTERNETS EGO WITH!!!!!!)

long live PCem

Reply 2 of 5, by wd

Posted on 2011-02-10, 23:59

wd Offline

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Joined: 2003-12-03, 21:23

You can use cycles=max or one of the advanced cycles configurations if you don't want
to mess around with exact cycles settings. Most newer games synchronize to non-cpu speed
related timers anyways.

Reply 3 of 5, by ripa

Posted on 2011-02-11, 15:08

ripa Offline

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3) How can I find out which is the maximum amount of cycles my computer can process? What happens if I keep increasing the maximum number of cycles with CTRL-F12 and step over this limit?

I remember seeing a patch on this forum somewhere that shows you how many cycles/sec dosbox is emulating with the cycles=max setting.

Reply 4 of 5, by FooAtari

Posted on 2011-02-11, 15:20

FooAtari Offline

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ripa wrote:

I remember seeing a patch on this forum somewhere that shows you how many cycles/sec dosbox is emulating with the cycles=max setting.

That would be pretty handy, I'll need to search for it

I've had a few late DOS Games that run on max cycles. And out of interest I've played with the cycles setting to see what was needed to run them.

Once game (Screamer 2) I set as high 200,000 cycles and it still wasn't as smooth as max...

Reply 5 of 5, by kolano

Posted on 2011-02-11, 17:39

kolano Offline

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ripa wrote:
3) How can I find out which is the maximum amount of cycles my computer can process? What happens if I keep increasing the maximum number of cycles with CTRL-F12 and step over this limit?

I remember seeing a patch on this forum somewhere that shows you how many cycles/sec dosbox is emulating with the cycles=max setting.

I believe there is a patch for such. I know the functionality is implemented in Ykhwong's build (i.e. from the menu Main\Show Details).

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