... theoretically - I wonder if the timing isn't too sensitive.
+3 ULA, which applies less contention than the 48K ULA (specifically, it ... applies contention only if ...

... , it is not running :(. 2T timing of read/write cycle is ... natural due to +3's ULA contention. Don't know...

... , it is not running :(. 2T timing of read/write cycle is ... natural due to +3's ULA contention. Don't know...
[/QUOTE ...

... I added support for Pentagon timing instead, so I can finally ... bus behavior and timing. An explanation how the ULA replacement fetches the ... bytes without any memory contention would ...

... developers to "see" what the ULA was doing. When port 255 ... data being generated by the ULA as it displays the screen ... .

13) The RAM contention models are different between the ... machines. This would only cause timing issues, not really a crash ...

... speed is controlled by the ula.[/QUOTE]

Errrr... no ... is there to deal with timing variances between different emulators.
contention being the obvious culprit here ...

... and no. Only when the ULA is drawing the screen and ... . For a full description of contention, I'd recommend that people ... avoiding screen tearing but the ULA doesn't contend with the ... you're really careful with timing you could synchronize your code ...

... cycles between interrupts. The memory contention timings are also different between ... read/writes combined with the timing tests to get an accurate ... are only 3 types of ULA (48K/128K/+3), frame ... [1] lets you know your contention pattern[2].

[ ...

... hacked some of Phil's contention testing code from fusetest that ... probes the contention pattern at a given tstate ... that one of the key timing routines needs to be called ... is that if the NTSC ULA just truncates the number of ...

... idea as A0 low means "ULA Port". However, additional lines can ... . This gave us the two ULA+ ports required.

... find out which port: standard ULA IO, Register select or data ... was trying to determine the contention timing for you all ;-)

... pixel display area to avoid contention with you wonderful chaps who ... , because we want to avoid contention with the palette updates. Loading ... the timing will be slightly different to a normal ULA in terms ... if we want to avoid contention. Doing so when the CPU ...

... -scanline and its affect on contention. My question then is, do ... sort out the behaviour and timing requirements. Some may not be ... remain compatible with the Spectrum timing.

But if built ... for the Spectrum, the new ULA will be used and bought ...

... />
If contention did increase, then either the ... two ways: increased contention or decreased contention.

contention behaviour is the reliance on the timing ... ULA had failed, then this signal timing would be affected, altering contention ...

... many as needed/possible given timing constraints:
2 bytes: address ... , but 8 down (subject to timing constraints).

I have ... would fit around the contention of the Z80/ULA or how many ...

... mistake, the ULA didn't apply enough contention to IO instructions ... the ULA to use the more conservative memory contention model ... of the intended IO contention model by forcing the ...
To maintain timing compatibility, the later ULA versions had to keep ...

... continue to do that! contention is evil, ULA is evil![/QUOTE]
In actual fact, the contention helps ... get your timing accurate to around 90% and the contention will automatically ...

... core and there the T80 timing issues come out. In fact ... a look at the signals timing (in particular) to the IORQ ... /> Are you using the original ULA contention algorithm (as described in Chris ... 't related to the T80 timing issues: I say that because ...

[QUOTE=Arjun;589491]Ooh! Shiny! Does this have the new ULA Plus timing that Andrew was working on?[/QUOTE]

I don't have special contention timings for ULAPlus. JSpeccy applies the appropiate contention for the ports used, and nothing more.

... has no memory contention, is this interface removes contention of +2? ... in ZX+2 is ULA with different screen timing, then show multicolor ... PROFI INTERFACE disable I/O contention on all ports(only ... used original memory and ports contention as on ZX128, or ...

... you preload/reset attributes before ula start drawing the new screen ... that I've lost the timing in the second row down ... -2 tstates. And due to contention, the sync will be lost ...

... being a DVI-D/HDMI ULA+ that can be plugged into ... on all Spectrums from a timing perspective - in other words, regenerating ... signal which goes away during contention periods - and therefore avoid the ... in time with where the ULA thinks that the TV scan ...

... being a DVI-D/HDMI ULA+ that can be plugged into ... on all Spectrums from a timing perspective - in other words, regenerating ... signal which goes away during contention periods - and therefore avoid the ... in time with where the ULA thinks that the TV scan ...

... for SPECTRA to operate (sync timing with ULA).
The SPECTRA manual ... -states pre-contention, and therefore know exactly where the ULA thinks the ...

... RFSH from CPU for eliminate ula effect known as "screen raining ... O ports slow-down CPU (ula slow-down cpu with same ... cause small incompatibility with original timing in some ZX demos...
contention:
[url]http://velesoft.speccy ...

... with Sinclair's ULA). This ULA has been cloned with ... , or even the different ULA, though?) with correct timings ... LIST]
[*] The contention pattern.
[*] Whether spurious contention is applied as ... ones.
[*] The timing of the first pixel read ...

... better knowledge than me about timing stuff in TK90X.[/QUOTE]
ULA timings, though! It seems the ... .e. Fuse) has a 'top_left_pixel' timing of 14362 for the 128K ... ,3,2,1,0,0 contention pattern starts at 8759 T ...

... =mcleod_ideafix;686350]
While the ULA is waiting for the time ... little contention.)[/I]

One mystery of the Spectrum ULA is ... byte as if no contention occured, although the timing would not be ...

... cockroach exists to fix a ULA bug, which is not present ... significant change over moving the timing of the second pair fetch ... timing in the ULA+ to reduce IO contention, it is important that the ULA ... chips, after startup, with zero contention - and it's a real ...

... is the timing between the 50/60 Hz interrupt and contention for ... 0x4000?0x7fff, detail of the contention pattern and its synchronisation, whether ... /03/temporizacao-de-video-da-ula-e-do-clone.html]my ... with the clone of TK90X ULA that was made by Fabio ...

... timing between the 50/60 Hz interrupt and contention ... 0x7fff, detail of the contention pattern and its synchronisation, ... temporizacao-de-video-da-ula-e-do-clone_27.html ... s data about TK90X ULA had been destroyed, as ... being employed in that ULA, but this has not ...