Evening people.
Do you remember when you loaded a game on the Spectrum or Commodore 64 and you used to get those lines on screen, (usually red or blue on spectrum and a mix of all 8 on the C64) well what were they? Did they serve a purpose or were they just something fancy to keep you occupied?

I know they weren't exclusive to these two machines but it was these two machines I saw them on the most.

not sure exactly what they were but they could help when you had to twidle the azimuth head screw.......they changed and you could tell if it was getting better or worse

speccy emus now you can choose whether to do the instant loading, or the proper 10 minute slow load with lines AND sound for the full nostalgia effect :)

Most of the time they were there to give you an idea that something was happening. :)

In some cases the electronics was manufactured down to a price, and one way to do this was to reduce the amount of what was called 'bus decoding' on the chips that handled input / output. The result of this was that it was possible for there to be 'bleedover', in effect, between different parts of the IO circuitry.

Some software fudges also caused this - I think it was, for example, the 'fast mode' of the ZX80 or ZX81 that flickered whenever you pressed a key - this was because of this sort of short cut between sofwtare and hardware.

They were very early versions of the visualisations you now get in media players.

When I thought who would reply, you two immediately sprung to mind. The trouble is guys, I'm none the wiser. :(

So they did serve some sort of purpose and weren't just fancy. Are you saying it was sometimes the bleedover being shown in visual form?

On the C64, I always took it as a helpful sign that there was something still being loaded from the cassette. On later games, the load screen would even display a proper image, with just the border colour-flashing. But all these were custom loaders, not the on-board C64 loader, so I presumed that part of the loading sequence was to keep changing the border and/or screen colour: after all, it would only take a couple of INC instructions?

EDIT: Just found this (http://www.pauliehughes.com/page3/page3.html) from a former developer. One thing he did in a turbo-loader was to just flash the border colour after every bit read from tape. Also, I'd forgotten the later development, where the loader would allow you to play a game like Space Invaders while you were waiting for the main game to load! Excellent stuff!

On the C64, I always took it as a helpful sign that there was something still being loaded from the cassette. On later games, the load screen would even display a proper image, with just the border colour-flashing. But all these were custom loaders, not the on-board C64 loader, so I presumed that part of the loading sequence was to keep changing the border and/or screen colour: after all, it would only take a couple of INC instructions?

EDIT: Just found this (http://www.pauliehughes.com/page3/page3.html) from a former developer. One thing he did in a turbo-loader was to just flash the border colour after every bit read from tape. Also, I'd forgotten the later development, where the loader would allow you to play a game like Space Invaders while you were waiting for the main game to load! Excellent stuff!

The guy who created the Ocean loader is a god in my house, I would happily give him my last Rolo.

The guy who created the Ocean loader is a god in my house, I would happily give him my last Rolo.

Just been looking at the code he's given for his loader for Rainbow Islands... brings back lots of memories of trying to hack into loaders/games! Some cool stuff - especially the anti-hacking code which might explain at least a part of my lack of success :hihi:

The guy who created the Ocean loader is a god in my house, I would happily give him my last Rolo.

I'd give him my last Rolo too, complete with rat poison! :rant:

I hated the multi-load system on the old Speccy games, having to load each level off a tape got annoying incredibly quickly iirc.

There was an element of deliberation about it, certainly on the Speccy. You could usually tell by looking at the screens whether the level was set 'right' for a tape to be read in properly.

But my (ancient) understanding was that soem of this arose because of the way in which the I/O decoding on the Spectrum was done with 1 8 bit IO address being used to listen to the tape, write data to the tape, read the keyboard and control the screen border colour. :)

Very cunning - but required you to do bit level AND and OR operations to make sure you only affected the correct bits.

http://www.nvg.ntnu.no/sinclair/faq/tech_48.html

Well thanks for the info guys. I'm none the wiser but I do sort of understand.

Rich, how dare you? That man provided me with many ( literally hours ) of fun loading screens to some great, great music. :D

I used to draw loading screens for C64 games.

I don't know what they were for, but I remember waiting 20 minutes for them to finish, only for it to crash and having to start all over again... :rant: :hihi:

I used to draw loading screens for C64 games.

Now that sounds interesting. How was it done? Did you have an art package or was it done by code or something? In other words, block 1 is red, block 2 is green and so on.

Rich, how dare you? That man provided me with many ( literally hours ) of fun loading screens to some great, great music. :D
I don't think Rich got what you were on about.

I remember invade-a-load fondly, I can still hear the excellent music in my head. I'd often start a game loading then stop the tape once the loading game came on. They were often more fun that the 'proper' game they came with:hihi:

Aparently slimsid invented the ZX Spectrum

Evidence here (http://www.nvg.ntnu.no/sinclair/stevo/specuser/clive.jpg) :)

Just kiddin slim :)

I always thought the loading lines on the Speccy were just a side effect of the incoming data affecting the timing and a certain port. The answer may be at www.worldofspectrum.org - have you posted the question Mel?

I don't think Rich got what you were on about.

I remember invade-a-load fondly, I can still hear the excellent music in my head. I'd often start a game loading then stop the tape once the loading game came on. They were often more fun that the 'proper' game they came with:hihi:

Invade-a-load ftw!!!
Remember the music mixer on the loader on Delta? Awesome stuff!
And Green Beret ... I used to stop the tape so I could hear the whole tune.

i cant fully remember how it went, but it was a similar idea to a barcode... something about how the red and blue lines spaced against each other, with yellow for tracking and green for binary... something along thoes lines any way..

Now that sounds interesting. How was it done? Did you have an art package or was it done by code or something? In other words, block 1 is red, block 2 is green and so on.

I had a touch tablet and art software. Quite primitive compared to today's stuff, but fairly advanced back then. There were restrictions though - you could only have 3 unique colours out of 16 in each character square, plus a global background colour. The resolution was very low too - 160x200.