Spectrum Computing

You can't. The processor only has a 16-bit address bus and that can only address 64kB of RAM. To do any more, you have to page RAM in and out within that address space. But from a plug-in interface, all you can do is replace the ROM in the lowest 16K of address space with one or more pages of 16kB o...

I see someone's gone round buying up all the Sony KDL-15G2000 tellies they can get their hands on. I wonder if they all came from big posh houses having their kitchens refitted like the ones I picked up!

It's not really warping. the bottle is erasing the pixels of whatever character cells are behind it, just leaving their PAPER colours, then drawing itself over the top in white INK. Berk does exactly the same around the edges; he's just a thicker chunk instead of an outline. Now look at Drut when h...

Theres a glass bottle in the game which isn't a solid mask like all the other items. So as Berk and Drut move behind it, you get that warped blob effect of colours. Not sure if its coincidence or genius, but I'm betting on genius. https://i.postimg.cc/kBz3rfyK/output-avi.gif It's not really warping...

A game where it bothers me a little is the dizzy games. I feel like it could have been handled better in those games. But I still love the spooky feel of them, that comes from the spectrum limitations. The white egg on a back background. It just is so spectrum to me. Later dizzy games on 16bit were...

Dark Sceptre was very blatant with the thick border, and it was a bit lame to have such a huge character in just one colour after that. Karnov tries to do a thick border on a small sprite, but (a) doesn't do enough, so it still clashes, and (b) still moves in jerky whole characters, so it looks dou...

The clue is for Codemasters' Monte Carlo Casino
Though I had to hunt around for a screenshot that looked like that.



I'd guessed something by Codemasters from the blue and yellow circles - should have searched more.

If 2 is Rifle Range then that's a pretty obscure one for a Carnival clone!

2. Rifle Range

Don't know about 'favourites'! As has been mentioned, in Manic Miner it's a handy warning that you're in trouble. Worst of all has to be 3 Weeks in Paradise where they really just don't care. I'd say that Dan Dare and Exolon have the best approaches. One using only solid squares of background colour...

I've got a DivMMC Enjoy Pro One somewhere, but I couldn't find it last night amongst all my other Speccy junk! :lol: I've got a ZX-HD, and successfully connected it to a 4:3 ratio monitor using an HD->DVI-D cable (though I also needed a mini HDMI adapter on the end of that). It doesn't have to be a ...

Yes. But the other problem is that access to that memory is still subject to slowdown even when it's not being used to generate the screen. In fact, 4 of the 8 memory banks all suffer the same slowdown of CPU read/write access that you might expect from video memory. Even worse, on one model of the ...

The video data is the first 6912 bytes of each of those two 16K memory banks. The first 6144 bytes is the 256x192 pixel data, followed by 768 bytes for the 32x24 character-cell sized colour 'attributes'. Memory Bank 5 is ALWAYS at address 16384. To access Memory Bank 7, it must be 'paged in' to the ...

To be honest, I really don't remember. I certainly had no idea about manipulating the stack to copy data. I had no idea where the stack was in memory when I was using it. I did have my own interrupt routines running and even some very basic multicolour stuff using LDI, but that was limited to someth...

Some 'interesting' choices made in the typography there - doesn't look like anyone ever stole it for a Spectrum game, at least.

I might try doing the Clementine tune on the AY chip too! The tunes that that .TAP file plays are, I think, the closest I can get to what I remember hearing. The really low versions are a triangular sound wave instead of an on/off square wave beeper, but I can only do that with the 128K sound chip o...

OH the NOES!!!

Juan F. Ramirez wrote: ↑Sat Jul 23, 2022 3:24 pm Not sure if this has been posted before, but... am I the only one who spots Donald Sutherland when watching Majik inlay by Mastertronic?

I'm getting a sort of highly made-up Bill Bailey!

I've been doing some tests to get familiar with the AY. This is just using a single channel and ramping notes up and down. For the kill-ghost I added a volume envelope too. I'm not sure I can do a pitch vibrato as in my game loop I'll only be accessing this routine at 25fps; I can't change the pitch...

I don't think that harmonic is making things any better. I thought it might have been a neat sine wave originally but I've since been convinced that the technology of the day must have used a triangular wave (if it wan't just square). Go to keep it simple. Try this - I've been doing some tests to ge...

It was GLUF that I was thinking of when it came to shifting pixels in multicolour! :D And I'm not ashamed to use 8x4 multicolour! The very last line of this screen is only 8x4 multicolour and there's no shame in that! :lol: (Mind you, there aren't very many pixels actually moving here either... :oop...

No, but if you put the attributes into the two screens and flick between them then the multicolour function is simply an OUT command every four pixel rows to switch screens. And that OUT command has the whole border space to trigger in, so the timing of it doesn't have to be anywhere near as accurat...

Can you post a picture of the other side, so we can see where all the tracks go?
Could one of the ICs be a resistor pack of some kind?

You simply can't write a machine-code monitoring program in BASIC.

The BASIC interpreter is itself a machine-code program, and runs tens or hundreds of times faster than anything you could do in BASIC. And every BASIC command you enact then needs a load of machine code to run to carry it out.

I don't think so. Most seaside arcades didn't put the fruities right at the front. I only remember hearing this on the street outside, where it was distinct from all the noises going on inside.

That sounds like the rhythm and the right sort of tone! Your description of a fairground organ is right, if a triangular wave can do that. Brilliant. I was just looking into how people have previously programmed the Speccy 128's envelope generator at high enough speeds to play triangular waveform ba...