Spectrum Computing

Yes, square waves have odd harmonics. That is, a perfect square wave is equivalent to a bunch of sine waves at 1, 3, 5, 7 … Infinity times the base frequency, tailing off in amplitude as it goes higher, all superimposed on top of each other. The Speccy beeper is far from a perfect square wave but un...

Announced on main Next and Next games facebook groups, Next forum and Next discord.

The Xberry Pi is a Spartan 6 FPGA clone of the ks1 Next issue 2B board, but sized and laid out to fit a Pi case. The extreme shrinking means some of the connectors and buttons are not present, or only present on pin header pads you can break out to connectors and buttons yourself. But because it can...

On some models of Spectrums the printer buffer doesn’t exist and has been replaced with additional sysvars. Amstrad did not care much about backward compatibility with the ZX Printer. If devs are going to the trouble to play nicely with BASIC it’s worth making programs play nicely on all models. Thi...

Even if you want to use BASIC and/or printing early on in your loading process, once you have called into your machine code entry point with USR, you can reclaim the remaining space by disabling interrupts and calling LD-BYTES directly from machine code, to load one final headerless block over the t...

Sure, send it my way by PM if you like. I have both ks1 and ks2 Nexts to test it on.

Devs and end users are treating N-Gos as functionally identical to ks1 Nexts as far as software is concerned, so we shouldn't expect any problems. Never hurts to check though!

Not a problem, I’m glad you solved it.

Ben does maintain a hardware cross-compatibility list but the ZX-VGA-JOY is not on it. I think it’s still worth talking to him so he can add your findings to the list.

It does make more sense now you said you’re using another external device that generates video output.

High horse?! Where are you getting that from? Just trying to help.

Why aren’t you talking to Ben about this? A brand new device should be tested, supported and under warranty. It’s definitely not normal for divMMCs to put anything on the bus for even numbered I/O port writes. Or to spam the bus when not asked to do paging operations, SPI operations or joystick read...

This ties in nicely with some experiments I was going to do. Nice!

A lot of people end up writing two emulators. One that loads and plays manic miner, and is very quick and enjoyable to write because the Spectrum is super easy to emulate. Then they start trying to make game X work, and game Y work, and find they need to emulate lots of technical machine-specific in...

It was not meant as criticism. It was fun to help!

You didn't say that the two greens were the part you thought was wrong. You just said it was not as expected. If you are specific with your questions then they almost answer themselves, or at least give people the chance to give you a fix wihout having to dig in and try to get inside your head.

I've been playing around with the Fujinet on the Atari 8-bits and there's some neat stuff available Fujinet is a little more ambitious, and gives you a full TCP stack like you had a PC network card. More like the Spectranet. Thom C is a talented bloke. The Next was saddled with a cheap ESP-01 modul...

BTW if you're not already using it, Remy's tool to tokenize basic and then export as a .tap is a helpful online way to try out these kind of code snippets in your favourite emulator without installing software or retyping.

https://zx.remysharp.com/bas/

Without redefining palettes it looks like this on a standard speccy. You printed in INK 0 and 1, paper 7, non-flashing and non-bright: https://dl.dropbox.com/scl/fi/9e8kq4nb7h26gabwhoi4d/ula-plus-palette-2.png?rlkey=c0ybgoben0vvha7tahezhr27j After running on a ULAplus capable machine it looks like t...

And the other obvious thing that bears spelling out is that attribute cells can still only contain one ink and one paper colour like a standard Speccy. And since both ink and paper in a cell shared the same flash and bright settings in a standard Speccy, in ULAplus that translates to both redefined ...

It is. The example linked to has the explanation and sample code to actually do it.

Maybe it would be better for Peter to ask specific questions about the parts of the explanation you don’t understand, and say what it is you doesn’t understand.

I never said it was an attack against the author. It's autistic people who aren't well served by that kind of unthinking treatment, not coders. You wouldn't say something was gay or retarded, or the person who wrote it was a spastic, without similar cringing all round. Even though those words have b...

Can't we just patch the tap to autorun at line 0? Is there a policy about not allowing things like that in the SC archive because they're not authentic?

I presume the skoolkit recipe can be fixed trivially to do this, and that's not the problem here.

I can’t see if anyone mentioned this yet but the cursor keys on every single Sinclair/Amstrad Spectrum model are in a horizontal row! Tastes and conventions change over the years, and have never been set in stone. Most people can adapt to different conventions without needing to resort to slurs abou...

You should check Manuferhi stock several times a week. He lists new units as he completes each tiny batch, and they sell out pretty quick. Richard Spencer has been ill and is currently in hospital, so you probably shouldn’t expect much new stock or orders to be fulfilled at Active Consult for a whil...

I’m not sure anybody is price gouging on these hobby design boards. The FPGA chip alone currently has a list price of £55 and a lead time of 12 weeks, so people still using Spartan-6 designs are mostly hunting around for small batches of reclaimed or resold chips at whatever the cheapest spot price ...

I know it was proofread, but I wasn’t on the proofreading team so I don’t know the details. I do know that it went to the printers 18 weeks ago due to printing deadlines.