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Delay routineAs some people are aware, I have recently starting writing a [url=http://fuse-emulator.svn.sourceforge.net/viewvc/fuse-emulator/trunk/fusetest/]autom…
... possible to reduce the minimal T-states. My program has a shortest ... run of 54 T-states, with CALL, RET and NOP ... added it becomes 89 T-states[/QUOTE]
Are you ... , i.e. 76 T without CALL, 93 T with it. And although ... -
A new Apple 1 emulator for the SpectrumHi all, I'm happy to announce a new Apple 1 emulator for the Sinclair ZX Spectrum! It's a port of Simon Owen's Apple 1 emulator for the SAM coupe to…
... noticed a remark about reducing T-states in the main loop.
T-states.
When B is constant ... code
in 26/36 T-states.
INC DE not ... mainloop, since this will cost T-states when your emulated code
Delay routineAs some people are aware, I have recently starting writing a [url=http://fuse-emulator.svn.sourceforge.net/viewvc/fuse-emulator/trunk/fusetest/]autom…
... /> ; bit0 set : 20 T
; bit0 reset : 19 T
.b1 ... /> ; bit3 set : 24 T
; bit3 reset : 16 T
.b4a ... *b2 + 8*b3 + 16*b4 T states
And we have ... loop takes 11+32*n T states, working off 32T for bits ...I'll name that game in ...I was about to recommend Astro Blaster to someone, when I realised it's not the game I thought it was. Astro Blaster appears to be a space invaders …
... a way that every 500 T-states the sound routine was invoked ... silly message). And it wasn't done for 'Crash'. This version ... some other. This version doesn't have any credits or an ... ) and Mike Webb (who isn't) wrote it. Not me.Preferred way of determining Y co-ord in assembly?I know of 2 ways of calculating the y-cord of a pixel row for the speccy in assembly. One is to calculate the address by ways of shifting and masking…
... the Min Size version (83 T States; no table) as although I ...Project: M.u.l.e.Wokani came up with a great idea about trying an open-development approach for spectrum games, and I thought why not try with a game I have under dev…
ok, I don't know why I didn't think of timing this ... scroll_isr() interrupt routine. Specataculator reports T states since the interrupt occurred (therefore ... 0 on interrupt) so the T state reading in Spectaculator's ...Project: M.u.l.e.Wokani came up with a great idea about trying an open-development approach for spectrum games, and I thought why not try with a game I have under dev…
... the memopd aswell. I don't have memopd in my tree ... the code later. I can't really see much of a ... you can work out the T-states and such :grin:
Project: M.u.l.e.Wokani came up with a great idea about trying an open-development approach for spectrum games, and I thought why not try with a game I have under dev…
... you can work out the T-states and such :grin:
[/ ... This all checked with Spectaculators T state counter, no mental gymnastics ... that an assembly programmer wouldn't normally use. A switch ... images, but I don't know without seeing the difference ...Z80 Developer ConsoleHi, This is a project I have meaning to do for ages, recently had a kid, had some time off work (as a software developer) and surprisingly had a bit…
... 'd like would be a T-state counter, which would show ... the t-state for each line of ... if they could print out t-states for each line of code ...Z80 Developer ConsoleHi, This is a project I have meaning to do for ages, recently had a kid, had some time off work (as a software developer) and surprisingly had a bit…
... (intellisense, jump-mapping, labels, defines, t-states and all that other good ...Contention and floating bus timingHello, I was recently playing a bit with memory contention and floating bus stuff in ZXDS and there is one thing which puzzles me a bit. It is the d…
... waiting a precise number of T-states before changing the border colour ... />
[QUOTE]the FAQ clearly states the contention starts at 1 ... ULA requires at least 2 T-states to read the display and ... . So at least 3 contended T-states must pass before the first ...Contention and floating bus timingHello, I was recently playing a bit with memory contention and floating bus stuff in ZXDS and there is one thing which puzzles me a bit. It is the d…
... /> [QUOTE]The first one can't be certainly contended by IO ... are contended at the 2nd T-state
- Ports with A0 ... A0 is low, the 1st T-state is also contended, 3rd ... /> -If A0 is high, all T-states are contended
But ...Contention and floating bus timingHello, I was recently playing a bit with memory contention and floating bus stuff in ZXDS and there is one thing which puzzles me a bit. It is the d…
... ]-If A0 is high, all T-states are contended[/QUOTE]
T states were contended, we would not ... pattern we can't tell anything about the 2 states after or ...Contention and floating bus timingHello, I was recently playing a bit with memory contention and floating bus stuff in ZXDS and there is one thing which puzzles me a bit. It is the d…
... -If A0 is high, all T-states are contended
[/QUOTE ... the first and last T states were contended, we would ... can't tell anything about the 2 states after ... about the 2 uncontended states may be true, however ... to tell how may T-states are contended by counting ...Contention and floating bus timingHello, I was recently playing a bit with memory contention and floating bus stuff in ZXDS and there is one thing which puzzles me a bit. It is the d…
... able to tell how may T-states are contended by counting the ... cycles. This doesn't tell us which T states were contended and by ... much, nor how many contended T states there are. Then we can ... the first and last contended T states, by running the instruction at ...Contention and floating bus timingHello, I was recently playing a bit with memory contention and floating bus stuff in ZXDS and there is one thing which puzzles me a bit. It is the d…
... also explain why it doesn't apply it during T3 and ... low at start of those T states (thus the snow effect) as ...Contention and floating bus timingHello, I was recently playing a bit with memory contention and floating bus stuff in ZXDS and there is one thing which puzzles me a bit. It is the d…
... also explain why it doesn't apply it during T3 and ... low at start of those T states (thus the snow effect) as ... byte fetches because there won't be time for the instruction ... wonder if the timing isn't too sensitive.
If ...Contention and floating bus timingHello, I was recently playing a bit with memory contention and floating bus stuff in ZXDS and there is one thing which puzzles me a bit. It is the d…
... least point out explicitly which T-states of the memory read/write ...Contention and floating bus timingHello, I was recently playing a bit with memory contention and floating bus stuff in ZXDS and there is one thing which puzzles me a bit. It is the d…
... contention during the following two T states, but this extending is what ... I haven't got from the schematics (yes ...Contention and floating bus timingHello, I was recently playing a bit with memory contention and floating bus stuff in ZXDS and there is one thing which puzzles me a bit. It is the d…
... least point out explicitly which T-states of the memory read/ ... and 128k, the only instruction T states which are not contended are ... and M3 cycles, all other T states are not contended (the ... case of any extra inserted T states the contention happens according to ...Can you write in the border?Is it at all technically possible in any way to get stuff into the border, apart from changing the border colour? I believe the C64 used the border a…
... , which take 11 and 12 T-states respectively. In the upper border ... pixels) is painted in 4 T-states, and on a regular Spectrum ... a one-off; you couldn't do that repeatedly to build ... a complete picture). I don't think anyone's ever attempted ...ULA RAS, CAS cycles, refresh and "snow effect"Hello everyone. I have a question, does anyone observed timings of RAS and CAS generated from ULA? I think there may be answer to where the "snow ef…
The direct bus or indirect one... that is the questionThe Ethernet project continues...and I'm in a quandry. So I've managed to implement enough socket library for the W5100 that socket, bind, listen, a…
... is that the chip won't need to be memory mapped ... take the same number of T-states as LDIR.
[/QUOTE]
The direct bus or indirect one... that is the questionThe Ethernet project continues...and I'm in a quandry. So I've managed to implement enough socket library for the W5100 that socket, bind, listen, a…
... reference code. Which doesn't actually use auto increment ... incremented when it shouldn't - but only during reads ... is many many more T-states than an INIR instruction!< ... in less than 50 T-states on average - at ... eat up 30-odd T-states including the c register ...Problem with replacing all upper memory with 4164 chipsGuys, i have a problem with the high memory of a 4B issue. At first the board had OKI chips for high memory and one of them was faulty. Since its ea…
... Z80 goes low for one T-state (the falling edge of ... full memory write is 3 T-states) which will be 285ns. /RD ... goes active for longer (2 T-states), but the actual important time ... , which is probably only 1 T-state. (Someone who's familiar ...another c64 vs. Speccy site...[url]http://c64vsspectrum.com/[/url] 25 years and we are still brawling.. ;)
... />
There's 224 T-states per scanline, so by the ... calculation, something like 7 T-states per 8 pixel long memory ... have less that 1 T-state per memory read ... used, the CPU wouldn't be able to access lower ... takes 3 T-states, and there wouldn't be 1 T-state to ...Detecting a Kempton joystick...I've been playing with the idea in the games I'm currently developing so that once the Kempston joystick has been selected you can hold FIRE down to …
... my stuff, unless you can't enable ints for some reason ... screen/attr bytes.
; (~14k t-states on 48k). Normal Spectrum ROM ...Bizarre stuff in Interface 1's shadow ROMAccording to the Complete Shadow ROM disassembly, the function that exits back to the BASIC interpreter after interpreting IF1 commands is this: [co…
... I missing? I just can't see any point however hard ... instruction. It just wastes 7 T-states as far as I can ...Bizarre stuff in Interface 1's shadow ROMAccording to the Complete Shadow ROM disassembly, the function that exits back to the BASIC interpreter after interpreting IF1 commands is this: [co…
... =Winston;250720] I just can't see any point however hard ... instruction. It just wastes 7 T-states as far as I can ... the solution, i don;t think 7 t-states would concern the authors ... ...afterall it isn't time dependant
