in the bottome 32k yes where the rom&speccy screen$ are but can the emulator explosion program be modified to do it? it already sdetects teh external ram
On 25 October 2011 14:02, Simon Owen <[email protected]> wrote: > Yes, you could certainly fill the top 32K with faster external RAM. Though > using Spectrum-compatible mode 1 does add extra contention stripes, so you'll > still get an extra hit on accesses in the bottom 32K. > > The current SDL version of SimCoupe uses 2048 samples, so it must have been > what I found as the best behaving too! Though I've always found SDL sound > more awkward to work with as it requests extra data as needed, rather than > providing a method to check the level and add more. I'm expecting to use a > mix of time stamps and buffer requests to trigger the next frame at the right > point, which should solve the 22-syncs issue you mention. It's a lot easier > with DirectSound as you have tighter control over the play+write cursors, so > you automatically get sub-frame accuracy (or you certainly used to – I've not > checked with Vista or later). > > I have an occasionally worked on source branch that's moving towards doing > that, though there are a number of related complications to untangle first. > One day... > > Si > > > On 25 Oct 2011, at 13:18, Thomas Harte wrote: > >> I think I'm right to say that external RAM can be paged into the top >> 32kb of address space. And it's presumably uncontended? So you could >> page some in and run a 48 emulator but everything would run at quite >> the wrong speed. >> >> Simon: I've always found 2048 samples to be the sort of level where >> most operating systems start playing nice with audio output; assuming >> 44100Hz output, wouldn't synchronising to that limit you to only about >> 22 synchronisation points a second? So frames would end up bunched >> together? >> >> Not really on topic, I admit, and the evidence that you know what >> you're doing is plentiful. I'm just curious. >> >> On Tue, Oct 25, 2011 at 12:38 PM, Roger Jowett <[email protected]> wrote: >>> key repeats? >>> >>> is it impossible to run 48 emulator snapshots in external ram? >>> >>> On 24 October 2011 14:35, Simon Owen <[email protected]> wrote: >>>> Hi Ian, >>>> >>>> I'm hoping fixed running rates will come 'for free' as part of the switch >>>> to audio-based synchronisation (rather than the current timer method). >>>> >>>> In the meantime, if you don't actually need the key repeats, try this >>>> patched ROM to disable them: http://dl.dropbox.com/u/2553707/norepeat.zip >>>> >>>> Extract it somewhere, then select it from Tools -> Options -> System (tab) >>>> -> ROM image. Reset the emulated machine to activate it. >>>> >>>> Cheers, >>>> >>>> Si >>>> >>>> >>>> On 23 Oct 2011, at 10:33, Ian Spencer wrote: >>>> >>>>> Hi Si, >>>>> >>>>> I'm sure you have been asked this hundreds of times before so I'll >>>>> apologise before I start but I've always used SIMCOUPE synchronised to >>>>> 50Hz with most programs and with others unsynchronised where the speed >>>>> was useful (especially with the program which I have used for years to >>>>> handle my bank accounts) and set the keyboard repeat rate to prevent >>>>> multiple key presses being produced. But the modern 3Ghz 4CPU machines I >>>>> now have are just so fast it's impossible to set the repeat rate low >>>>> enough. They are just too fast and as many programs are much more usable >>>>> when the speed is 200 - 500% above the standard it would be really >>>>> fantastic if this was in some way selectable even if at this speed the >>>>> instruction timings weren't very accurately scaled. >>>>> >>>>> Best wishes, >>>>> Ian Spencer >>>>> >>>> >>>> >>> > >
