# 05 - And a whole byte is not enough ... | Anime

Today, the topic of the release of the ICBM will be ... ANIME. The same thing that is usually discussed on irc-channels about FreeBSD, in between kernel patches. And we will return back in time back to February 1999, that is, twenty-one (!) Years ago.


Before us is a Locomotion video disc for the ZX Spectrum 128K + disc interface. The authors of the conversion are two simple Samara guysalkoro and unbeliever, but it was like that ... After working Blame for demopati Funtop'98, we learned how to easily operate with video fragments from the Spectrum RAM. The clip with Bill Gates was not a great achievement, but even today it looks pretty decent, especially if you move away from the screen and keep in mind that all the data at the time of the video is in 128K RAM.



Six months after Funtop'98, in the midst of an economic crisis, we mastered non-standard ways of working with a drive. Many have spied on Refresh , Condommed, and other similar releases loading data from media without a pause in the work itself. The idea of ​​loading data from the drive to the music, without interrupting the display of work, was so exciting that I wanted to try it immediately. This is how this technical demo appeared, based on the original video:



The original of 1989 from Pacific Data Images was quite a cult status in the old days for PC users. This video was on everyone’s hard drive and was often used to benchmark the performance of the video card, especially after the upgrade. The main goal was to play the video in full screen. If your S3 Trio video card "pulled" a full screen when playing this video - you were the first guy in the area. Let me remind you that the mass release of DivX-based video to the market took place in the summer of 1999, and at the time of the release of our release for ZX Spectrum, it was virtually impossible to watch movies on a PC. Well, maybe the VideoCD is encoded with a lightweight MPEG-1 or a bit heavier MPEG-2.



The Locomotion (ZX) start screen provides comprehensive technical information. Work takes one five-inch DS / DD floppy disk, each frame is 64x42 pixels (more precisely, chunk), the point is encoded in three bits of gray, the video has 6 fps, and the total number of frames is 778. We were forced to use custom disk layout for two reasons. Firstly, all frames did not fit in 640 kilobytes of standard markup. Secondly, there is an order of magnitude more interesting! We partitioned the floppy disk so that each sector contained one whole frame of video and this allowed us to significantly increase the frame-rate up to the coveted 6 frames per second, which is very decent for an eight-bit machine ...

That's all for now! We have a very busy schedule for the next 24 hours in preparation for Revision Online 2020, but I will definitely supplement this article with source codes and other details closer to Saturday!

Add to bookmarks, come back, re-read later ...

UPD: Yes, the source code of the code has been preserved with us. Everything compiles, the freshly compiled code starts directly from XAS, plays white noise in 1/4 frame, since the sector of the disk is 256 bytes in the emulator. Then everything returns correctly to the main menu, then to XAS, and in the main source loop is commented out, especially for debugging. Also, a source code was found which encodes video from PC frames converted from PC - this is a real monster, 4 times more than the locomotion itself in the code. The sad thing is that the original frames of LOCOMOTION c PC were lost, from which theoretically it would be possible to assemble the entire project again. However, this is not our goal.

Open questions to those who can ZX Spectrum:

Need help - how to access files inside SCL / TRD on a PC and convert the XAS source to plain text?



--- EOF ---

#FF - And a whole byte is not enough ... | Pilot)
# 00 - ICBM ... | Invitation to Revision Online 2020
# 01 - IBMP ... | What are intro?
# 02 - The MBM ... | The Cross of Changes
# 03 - IBMP ... | 2B or not 2B
# 04 - IBMP ... | We take BC by the horns
# 05 - ICBM ... | Anime
# 06 - IBMP ... | Meteorisms
# 07 - The MBM ... | Revision Online

Grandfather's Telegram Entertainment Channel:teleg.run/bornded

There is a chat next to the channel. In it, you can try to raise questions for the demoscene, assembler, pixel art, tracker music and other aspects of the processes. You can be answered or sent to other, more thematic chats.

So they won - so we win!