Spectrum Computing

That doesn't mean they could have afforded the £175 in the first place. The entire point of the machine was that you could upgrade later, reducing the initial outlay. since the upgrade orders began pouring the same summer (adding to the number of frustrated customers waiting for the deliveries) thi...

1 in 3 of all Spectrums sold in the first 16 months were 16K - that's £20 million at £125 each. afaik prices were down (to £99 and £129) after 12, not 16 months You're either assuming that those 160,000 16K Spectrum buyers would have simply found another £50 and bought a 48K model instead, well, ma...

The fact than many 16K machines were upgraded, and that there was no competition (due to the 16K undercutting the nearest rival by £50), means the model was successful, not that "Sinclair got it wrong". Now you're getting it wrong. The question is not about if 16K was "successful&quo...

The 16K model alone ended up selling over 200,000 units though even if it's correct, still a fraction of the other models, and many of these were upgraded to 48k though, starting mid-1982 - around the same as the Acorn Electron or the Dragon 32, one of the Spectrum's early rivals. Without the £125 ...

I'd kind of disagree here. I think one of biggest reasons the Spectrum (and previously zx81) were successful, is because Clive managed to manufacture down to a 2 figure price ( £99 ) - which would have been the deciding factor in loads of kids actually getting a computer - which made them popular, ...

for me the Sam Coupé always looked overengineered and underpowered (even more than the Amstrad CPC)

I believe the goal was to create very quickly a cheap/affordable machine for everyone . Better specifications would mean : 1. More design time 2. More expensive 3. Would be starting to compare spectrum with "higher specs" machines. (eg why 64k and not more etc..) If #3 would happen then #...

Probably the simplest way to get rid of the colour clash (and to make more and better looking game conversions possible) was to add another mode with a bigger and improved ULA - low-res 4 colours 4x8 tiles (with rectangular pixels - common for many other home computers). It would use the same screen...

there's another option missing: Sinclair got it wrong starting with just 16K, the 1st model shoulda be 48K+

Many of the original hardware addons only decode xxxxxxxxxxxxxxx1 or xxxxxxxxxx0xxxxx. That's not terribly useful if you have any other hardware connected (especially the three Kempston mouse ports based on the same scheme), so Velesoft suggests that modern hardware and emulators do a more full (bu...

Almost no real hardware implements Kempston 55 though. do you mean decimal 55 = binary 00 1 10111 ? thought the original hw checked just one bit #5 to be zero in the io address some simplest clones will read kempston at any odd port number other ones may check 2 or 3 bits masking out the rest prope...

Jbizzel , i tried it once. The main problem of Bomb Jack is not the negligible colour clash (sprites are mostly black anyway) but the way it combines erasing the old sprite and drawing the new one accidentally destroyng parts of the already drawn sprites under it. While it is possible to minimize t...

more games - Bangers & Mash - a multiload, but such a simple dux works for the both parts the Happiest Days of your Life turned out to be a very interesting case where Spec256/ZX-Poly bitplane-painting approach may fail even with uncompressed pixel data. The sprite mask is generated on the fly w...

Intensity
Capitan Trueno (p2)
Mot (p1)
Ulises (and maybe some other Opera games)

@ballyalley, have you tried pressing LEFT (on the stick) to start (instead of the usual fire/space)?

Frightmare (128k version) - https://spectrumcomputing.co.uk/entry/1877/ZX-Spectrum/Frightmare this one went surprisingly fast and smooth, except some of the original sprite masks defects revealed ; buf2scr 1099BE 0111 0 1099C0 1099BE 3D ; sprite 109842 C30F 109848 0140 0 0 0150 0 6077 0160 109861 5...

a quick work for la Bruja aka the Evil Spell https://spectrumcomputing.co.uk/entry/23954/ZX-Spectrum/La_Bruja ; sprite 108474 01F0 05F0 0 CF1F 10847C 0131 C333 0 0013 80847D 0 FFFF FFFF FFFF FFFF FFFF FFFF FFFF 1084B0 C3CA 1084B1 0130 5F33 0531 0 0 0 0330 0 0 0 0113 1084BF C888 ; sbuf2scr 1085A7 013...

i'm not sure if it looks better than the original (esp those solid-color slopes/corners and all-white sprites)

marenja wrote: ↑Sat Nov 19, 2022 9:26 am https://spectrumcomputing.co.uk/entry/5 ... m/Thanatos
Which version is unrolled and faster ?

not here, as these are official tape versions, check this one
https://zxart.ee/rus/soft/game/arcade/a ... anatos-ay/

Lethargeek wrote: ↑Fri Oct 28, 2022 9:46 am a hacked Flying Dragon

i meant Thanatos)) it was another hack that was called Flying Dragon

The CPU is no faster and that is probably the biggest bottleneck on an 8-bit machine. Now having a wealth of extra RAM available might mean you can speed processes up by pre-computing large tables of data or storing more data uncompressed (or pre-shifted etc) to reduce the amount of on the fly comp...

An easily understood (though not hugely efficient) way to compress a screen that's got lots of empty character cells is to start with the attributes, and exploit the fact that no-one in their right mind would ever use the FLASH bit. So you scan your screen for empty character cells, and if you find...

It is not always good. For example, "Mask 3: Venom strikes back" have additional file for 128K loading (main menu AY music). So, 48K does not load this part. https://i.imgur.com/CRQL23n.png well, nobody is stopping you from saving sna every time the condition is met and then pick the last...

Using an emulator as you've described is all well and good, but it's not a technique that lends itself to scripting and automation. That's what I'm aiming for with the --sim-load option of tap2sna.py . But you may apply the same logic to your script, not limiting it just to the ROM loaders.That is,...

i use "exit subroutine" button in SPIN debugger
then trace the PC until it points into the RAM
(trapping USR ROM routine for BASIC loaders)
it works for non-ROM loaders as well

and just to be sure nothing below the stack is corrupted
trace until the stack pointer moves for 48k snapshots