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CPU speed measure possible?Is it possible to measure the CPU speed and shows the result on a LED display? Micky
... direct from Xtal, the other ('contended') one from ULA. We don ... -
DivIDEo - streaming video on the DivIDEThis has been a bit of a personal holy grail for years and years, so I'm very pleased to announce the release of DivIDEo, my streaming video system f…
... something to do with avoiding contended port reads during INI instructions ... -
Who can fix my Flash programmer code?I have a problem with some code, it doesn't work and I don't have any idea what it's trying to do, or failing to do! The code in question is the fla…
seems being the operative word...
the tape routine is running in contended ram so breaks, but for some reason it worked in spin!
also there are bugs in the flash erase code somewhere, back to the drawing board :) -
So you need to double (or triple, or quadruple) the clock speed...No particular reason for posting this, other than I was looking at an eZ80 evaluation board that does this, and that jogged my memory of a project I'…
... ULA (both VRAM and non-contended RAM), and I'm afraid ... other way, if a non-contended RAM access is to be ... -
+2A extended memory map & ULA bug?The [URL="http://www.worldofspectrum.org/faq/reference/128kreference.htm"]128K reference page[/URL] says: [quote]The ULA bug which causes snow when I…
... mode, with RAM bank 4 (contended memory) in 0x0000-0x3FFF, and ... -
"Programming the Spectrum in Assembly" series in Micro MartI see that Shaun Bebbington is starting a series of articles in Micro Mart magazine on how to program in assembly for those who might know a little b…
... previous models, since every 8 contended states there's only one ... -
Sprite MaskingI was looking at the sprites in some games, and noticed they have sprite followed by mask. Usually a row at a time (so the mask is sort of interleave…
... use the block load instructions (ldi, ldd, ldir or lddr) ... simple 8x8 pixel sprite. LDI will do the following for ... ld a, (hl) ; part of ldi
ld (de), a ; ... part of ldi
dec bc ; part of ... an effect of [b]ldi[/b] that in this ... -
Sprite MaskingI was looking at the sprites in some games, and noticed they have sprite followed by mask. Usually a row at a time (so the mask is sort of interleave…
I quite agree that using LDI is faster than using the ... -
"Programming the Spectrum in Assembly" series in Micro MartI see that Shaun Bebbington is starting a series of articles in Micro Mart magazine on how to program in assembly for those who might know a little b…
... previous models, since every 8 contended states there's only one ... -
Sprite RotatingI was looking (actually at Everyone's a Wally), and noticed that all the graphics for the main characters are left facing, and two characters wide. …
LDIR timings in contended RAM?The 48K Spectrum technical reference page ([URL="http://www.worldofspectrum.org/faq/reference/48kreference.htm"]here[/URL]) describes the detailed ti…
... note is that contended memory is not actually contended until the ULA ...LDIR timings in contended RAM?The 48K Spectrum technical reference page ([URL="http://www.worldofspectrum.org/faq/reference/48kreference.htm"]here[/URL]) describes the detailed ti…
... ]) describes the detailed timings of contended RAM. It gives timings for ... residing in, or reading/writing, contended RAM.[/quote]
You ...LDIR timings in contended RAM?The 48K Spectrum technical reference page ([URL="http://www.worldofspectrum.org/faq/reference/48kreference.htm"]here[/URL]) describes the detailed ti…
... PUSH, only the plain old LDI. Stack is used, but in ...LDIR timings in contended RAM?The 48K Spectrum technical reference page ([URL="http://www.worldofspectrum.org/faq/reference/48kreference.htm"]here[/URL]) describes the detailed ti…
... , using a sequence of [b]ldi[/b], assuming there would be ...Beepola v1.01A new version of Beepoa, v1.01, is now available for download from:- [URL]http://freestuff.grok.co.uk/beepola/Beepola_v1.01.00.zip[/URL] (650KiB) …
... ROM). The problem is that contended memory access isn't just ... square-wave tone channels) in contended memory. It sounds pretty funny ...Beepola v1.01A new version of Beepoa, v1.01, is now available for download from:- [URL]http://freestuff.grok.co.uk/beepola/Beepola_v1.01.00.zip[/URL] (650KiB) …
... ROM). The problem is that contended memory access isn't just ...Beepola v1.01A new version of Beepoa, v1.01, is now available for download from:- [URL]http://freestuff.grok.co.uk/beepola/Beepola_v1.01.00.zip[/URL] (650KiB) …
... square-wave tone channels) in contended memory. It sounds pretty funny ...A question about M1 cyclesI'm writing an interrupt routine that, after the usual register pushes, will jump to a location of my choice with a [b]JP (IY)[/b] instruction. If I…
... table will reside in non-contended memory, somewhere in the address ...multicolor on 48Kmany people tried multicolor 8x1 on 48K model and ended with maximum width about 18 chars. yesterday i tried [b]8x2[/b] on 48K and achieve 24 char wi…
... , you really get hit by contended memory.
(The one ...Silly question on Russian clonesIv a silly question to ask... Iv been looking at web links about Russian ZX clones with envious eyes, wondering if I might spend money on something…
... ULA timings except for the contended memory -> [url]http://translate ...Cant DecideI have had a lot of spectrums in my time from the 16k to the +3 and as we all know they all have flaws. I am thinking about buying another and wanted…
... games are written for the contended RAM of the +2A and ...Embedding external code in Z88DK projects (Beepola related)Hi all, I've been doing a few things in Z88DK, but I was wondering how I could link binary data compiled separately into my projects. Specifically I…
... your song isn't in contended ram though. 32768+ is okay ...Memory mapping: Pentagon compatibility?I'm writing something that will rely heavily on the Spectrum's ability to switch screen buffers in hardware (port 0x7FFD). The original Spectrum 128K…
... . The Russian machines have no contended RAM to worry about. The ... both video RAM pages are contended. The standard Pentagon doesn't ...Memory mapping: Pentagon compatibility?I'm writing something that will rely heavily on the Spectrum's ability to switch screen buffers in hardware (port 0x7FFD). The original Spectrum 128K…
... the pages that are not contended on any of the 128s ...Memory mapping: Pentagon compatibility?I'm writing something that will rely heavily on the Spectrum's ability to switch screen buffers in hardware (port 0x7FFD). The original Spectrum 128K…
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Port 0x7FFD is itself contended, and horribly so. I only ...Memory mapping: Pentagon compatibility?I'm writing something that will rely heavily on the Spectrum's ability to switch screen buffers in hardware (port 0x7FFD). The original Spectrum 128K…
... ;464692]Port 0x7FFD is itself contended, and horribly so. I only ...Z80 Machine Code Question...Hi Folks, I know not strictly a BASIC question but I have started to learn Z80 machine code - 25 years too late! :smile: I have been reading a book…
... to copy (HL) to (DE). LDI automatically increases HL & DE ... , and the repeat part of LDI[B]R[/B] makes the ...Using the stack to copy memory blocksA [b]PUSH[/b] and a [b]POP[/b] instruction together take less time than two [b]LDI[/b], so long [b]POP/PUSH[/b] sequences are sometimes used to copy …
... better than penalty for two LDI. that is where you get ...
