Spectrum Computing

Difficult to say without seeing the code. Perhaps you could post it somewhere so people on here can take a look?

+1 to what [mention]akeley[/mention] said. As has been demonstrated countless times in the past, Lee and his clique aren't interested in a rational discussion, so arguing with them is a waste of time. Other than that there's no need to defend yourself [mention]Einar Saukas[/mention], you've done mor...

It's especially helpful in cases like the one you were struggeling with with "and 31" and "first 8K of ROM". The decimal numbers 31 and 8191 tell you nothing. 0x1f and 0x1fff on the other hand immediately let you see that you don't need to worry about the low byte. Or take PeterJ...

"8K" = 8192 bytes. So the first "8K of ROM" means an address between 0 and 8191. 8191 = %11111 11111111, or 0x1fff. We don't need to worry about the lower 8 bits, since they may take any value. The upper 8 bits on the other hand must have a value between 0 - %11111, or 0 - 0x1f, ...

a) does this have bias on larger numbers (ie. if a>=31; AND 31 would always equal 31 ???)? No. A logical AND operates on individual bits. The result of ANDing two bits is 1 if and only if both of the pair of bits are 1. %00110001 (= 49 decimal) AND %00000111 (= 7 decimal) ========================= ...

Thank you @utz. I will need to look at that one written down in binary so I understand! Hehe, I was thinking whether I should give an explanation, but I figured you could work it out on your own. And ideed you immediately had the right idea: Looking at the number in binary will give you the answer ...

Thanks @bob_fossil You made me have a thought. I foolishly forgot that the grey is paper white without the bright. Apologies. I will look at the option you suggest, which would certainly be an improvement. So if I create a random number between 0 and 7 with and 7, then do a bit rotate 3 times would...

A round of appreciation for Einar's z80table! Opening that up is pretty much always my first action when doing any serious Z80 coding.

Ha, you're a machine. Thanks a lot. I think with this setup, only minimal changes will be required on the Bintracker side, as I can send pretty much the same messages that I'm sending to MAME. Just need to write a Tcl script to decode them on ZXEmuT. That'll be fun.

On second thought, it actually doesn't need to work on Windows. MAME will stay the default for Spectrum emulation, with ZXEmuT being an additional option. Windows users will miss out on it then, but well, tough luck :D If you could implement calling Tcl code on hitting breakpoints, that would be awe...

A Tcl interpreter, you say? Excellent! That should be quite workable. I'm controlling MAME through a stdio pipe. I could in theory do sockets, but it needs to work on Windows as well, so pipe is easier to do for me, I believe. One feature that would be great to have is to be able to execute code on ...

Is it possible to control ZXEmuT through stdin? If so, I could actually use it as an alternative to MAME in my Bintracker music editor.

What a waste. That key should be remapped as a second Ctrl key, of course

So no-one indenting for loops, conditional code etc ??? it is not even always possible, considering that jumps can create a fine web. it is much easier (and cleaner, i believe) to split the code to "logical blocks" with empty lines. Exactly, it's not always possible/useful to apply best f...

Ah yes, I studied Zymosis quite extensively when I wrote my own z80 emulation library a few years ago. It's an excellent piece of code. Glad to see you're still working on it.

OK, that shouldn't be a problem. I think using LGPL may complicate things given that the Spectrum that doesn't any formal kind of dynamic linking, unless you count something like including the player as a separate block on the tape. I have changed the license to 2-clause BSD, is this acceptable? Gr...

It just occured to me that I didn't voice my excitement about this yet! So: This is a fantastic project, I love it! I would actually want to support the driver in my upcoming new tracker/chiptune audio workstation . However, I have some concerns regarding the license. Generally speaking, chip music ...

* You can try to speed up the spectrum to fit the right number of Ts in one vertical frame and halt the clock during portions of the horizontal scan to match the hdmi horizontal rate. This doesn't work either as it breaks audio. Beeper sound is sh*t and ay doesn't work for sampled music or stuff th...

Ast A. Moore: Some nice voodoo with parity there ;) But looks like it doesn't produce the desired output, unfortunately. djnzx48: Hmm, maybe I should've just posted a naïve asm implementation instead of being clever in the middle of the night. In any case, your second snippet does the right thing. S...

Hi, Been twisting my head over this little assembly problem for quite some time without much progress. I have a nested conditional that I want to calculate as fast as possible and in constant time . Assuming three 8-bit integers a , b , and d , I want to calculate the following: if (abs(a - b) > d) ...

Very kind of you wanting to credit me for this Just "utz" is fine, or if you like you could throw in a link to my website, https://irrlichtproject.de.

Besides the Computerspielemuseum, there's also the Signallabor at Humboldt University. Not sure if they have any GDR Speccy clones, but there is at least one KC85/4 ready to be used ;) It's a semi-public place, so best to make an appointment with Stefan Höltgen before visiting. He also does some the...

Perhaps not so useful for most coders, but I often use 2 of them in sequence for timing purposes. Just 2 bytes for wasting 38 t-states - can't get any more bang for the buck than this on Z80.

Distribution of PASMO without source is technically also illegal, since it's released under GPL.

Excellent write-up, I'm thoroughly enjoying this. Gears creaking quite a bit in me ol' brain, but so far I could mostly follow your explanations.