█ slanina

16-08-2020   Rolling continues

Here's remix of Roll me gently - an 4k invitation to SPECCY.PL PARTY 2020.1 . There are a few more(than in the 256b version) effects and an amazing AY tune made by MCH. Intro was released on Decrunch 2020 party. Unfortunately it wasn't shown in ZX Spectrum 48k Demo compo (due to the usage of some ZX 128 fetures ( screen banking )) and was moved to the Wild Demo compo, where got 8th place.

RMG Remix 4k @Pouet
RMG 256b intro @Pouet
Source code of the 256b intro @Github

The chessboard and tubes are based on simple counter and different (per pixel) increments. Let's explain how it works:
Prepare a screen-width size input buffer (256 bytes on ZX Spectrum) and fill with 'single step'(1) counter inc value:

`1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1`

To make a pixel data from the above, use simple loop with bit n (n=2 in this case) of counter used as a color indicator:

```x = 0
counter = 0
while( x < width ) {
counter += buffer [x]
screen [x] =  (buffer & 4) ? 1:0
++x
}
```

The result array (screen[]) should be filled with data:

`1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0,1,1,1,1`

Here's better visualisation of it:

Each 'tube' is defined as a dataset:

`5,4,3,3,2,2,1,1,1,2,2,3,3,4,5`

To draw a tube, place the data somewhere in the input buffer:

`1,1,1,1,1,1,5,4,3,3,2,2,1,1,1,2,2,3,3,4,5,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1`

Result array after executing the counter loop:

`1,1,1,1,1,1,0,1,0,0,1,1,0,0,0,1,1,1,0,0,0,1,1,0,0,1,0,1,1,1,1,0,0,0,0,1`

Next step - expand (copy) the result array down the screen.

To get the final effect - invert some lines. On ZX Spectrum is done by change the attributes - swap PAPER and INK values ( 256b intro) or by invert the pixel data (4k intro )

Does it look familiar now ;) ?

14-08-2020   MacBook battery. 5 years later.

After five years of heavy use, my Macbook Pro (Early 2015 model) began to bulge around the touchpad. The diagnosis was obvious - the battery. So, I followed the guide at iFixit. The whole process was quite easy and it took me 20 minutes to replace the battery.

26-07-2020   Roll me gently

A tiny bit of Z80 asm code for ZX Spectrum. Here's my entry for 256 byte compo @ flashparty. Ranked 2nd. I'll upload source to GitHub soon.

17-07-2020   Kimme & Korn [Merkur 199?]

Hardware: 68k + HD63484 + (guess) 8051 mcu (controlls). So, basically the "Shooting Star" hardware without the Art&Magic video board. Doesn't work yet, due to missing controlls / comms and (probably) incomplete dump.

15-07-2020   Infinit! [Chyron 198?]

Character generator with interesting components:

• 80C186XL20 - CPU
• COM90C26 - Arcnet Controller
• COM90C32 - Arcnet Controller
• M68HC16Z1 - MCU (romless)
• HD44100H - LCD Driver
• HD44780A00 - LCD Controller
• NS S9252AL - ?
• 4xP8251A - USART

12-07-2020   Another 'spare time' project.

Simple mobile game with classic arcade feel (i hope) ... without name (so far).