ped7g

; Authors: Omega, Ped7g, Baze ; (C) 2021 ; license: https://opensource.org/licenses/MIT
; Z80 assembly, syntax for sjasmplus: https://github.com/z00m128/sjasmplus
; to assemble run: sjasmplus omega_fades.asm
    OPT --syntax=abf
    DEVICE ZXSPECTRUM48,31999
    ORG $8000

;------------------------------------------------------------------------------
; ULA attributes "fade out" effect, going through PAPER/INK values,
; decrements them (individually) by 1 every iteration (call of routine)

ped7g

; (C) [copyleft] 2021 Peter Helcmanovsky
; License: CC0 https://creativecommons.org/share-your-work/public-domain/cc0
;
; x86_64 linux asm example of base64 encoding
;
; reads stdin, encodes it to base64 without new-lines, outputs to stdout
;
; the code is meant to be rather straightforward and simple (for lecturing purpose),
; not performance optimal
;

ped7g

    DEFINE USE_DMA_TO_CLEAR_SCREEN  ; comment out to get LDIR clear version
    DEFINE USE_DOUBLE_BUFFERING     ; comment out to see single-buffer redraw issues

    DEVICE ZXSPECTRUMNEXT

BORDER  MACRO color?
            ld  a,color?
            out (254),a
        ENDM

ped7g

;; original facebook post in "Z80 Assembly Programming On The ZX Spectrum" group:
; Here's a challenge for your creativity.
; Create a Z80 assembly function with the following properties:
; Input in A: values in the range [1,32]
; Output in A: 1 for 1-8, 2 for 9-16, 4 for 17-32
; No loops or other conditional jumps.
; No usage of ROM code.
; No comparisons.
; The function will map how many bits an integer needs to how many bytes it needs in a typical C style struct.

ped7g

; ZX SPECTRUM code, sjasmplus syntax: https://github.com/z00m128/sjasmplus
; alternative code for Allan Turvey post: https://www.facebook.com/groups/z80asm/posts/1982356728824612/
    ORG     $8000-8
    DEVICE ZXSPECTRUM48, $ - 1
size_start:
    dg      ...#.###
    dg      ....####
    dg      ...#####
    dg      ...#####
    dg      ..######

ped7g

; Author: Ped7g ; (C) 2022 ; license: MIT / GPL / Public Domain (pick whichever fits best for you)
; assembled with: https://github.com/z00m128/sjasmplus/
; based on https://github.com/MartinezTorres/z80_babel project, written as comparison
;
; Notes for myself about debugging/verification: in CSpect debugger `SAVE "data.bin",from,length`
; Then `hexdump -v -e '/2 "%u\n"' DATA.BIN > data.txt`. Then compare with `sort -g data.txt`

    DEFINE ORG_ADR $8080    ; using only uncontended faster memory, but smaller buffers

    OPT --syntax=abf : CSPECTMAP "qsort.map"

ped7g

; (C) [copyleft] 2018 Peter Helcmanovsky
; License: CC0 https://creativecommons.org/share-your-work/public-domain/cc0
;
; x86_64 linux asm example of fixed-point arithmetic
; (see https://en.wikipedia.org/wiki/Fixed-point_arithmetic)
;
; to build I'm using nasm and ld:
; nasm -f elf64 %f -l %n.lst -w+all; ld -b elf64-x86-64 -o %n %n.o
; (where %f is source file name and %n is just the main part w/o extension)
;

ped7g

; Author: Ped7g ; (C) 2022 ; license: MIT / GPL / Public Domain (pick whichever fits best for you)
; sort array of pointers to 64 char long strings (for example filenames)
; assembled with: https://github.com/z00m128/sjasmplus/

    DEFINE ORG_ADR $8080    ; using only uncontended faster memory, but smaller buffers

    OPT --syntax=abf : CSPECTMAP "qsorts.map"

    DEVICE  ZXSPECTRUM48, ORG_ADR-1
    ORG     ORG_ADR

ped7g

; ----- Colour palette (ULA)
BLACK			equ 0
BLUE			equ 1
RED				equ 2
MAGENTA			equ 3
GREEN			equ 4
CYAN			equ 5
YELLOW			equ 6
WHITE			equ 7

ped7g

; (C): copyright 2022 Peter Ped Helcmanovsky, license: MIT
; name: custom ZX Spectrum ROM to measure time until first /INT signal
; public gist somewhere at: https://gist.github.com/ped7g (search for it)
;
; to assemble (with z00m's sjasmplus https://github.com/z00m128/sjasmplus/ v1.20.1+)
; run: sjasmplus rom_first_int.asm
;
; history: 2022-08-23: v1.0 - initial version
;
; purpose: