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

; 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_2.asm
    OPT --syntax=abf
    DEVICE ZXSPECTRUM48,31999
    ORG $8000

    ; uncomment and set to available SCR file to run the effect on ZX screen image (6912 bytes)
;     DEFINE SCR_FILE "diver - Mercenary 4. The Heaven's Devil (2014) (Forever 2014 Olympic Edition, 1).scr"

ped7g

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

; D:E = field height:width, A = attribute, modifies: AF, HL, BC, IXL
drawCheckerboard:
    ld hl,$5800
.alternateLine
    xor $40     ; alternate BRIGHT 1

ped7g

; Author: Ped7g ; (C) 2021 ; license: https://opensource.org/licenses/MIT
; Z80N (ZX Next) assembly, sjasmplus syntax: https://github.com/z00m128/sjasmplus
;
; code-size optimisation for larger next-reg init block, where `nextreg r,v` ED91rrvv
; opcode takes four bytes for every next-reg set, so a block of 20 pair values takes
; 80 bytes (with the "setup_next_regs_v2" approach such block will take only 58 bytes)

;----------------------------------------------------------------------------------------
; variant 1, reads next-reg pairs from particular memory address
; this will break-even at 8 value pairs, every one more pair is two byte less

ped7g

; the macro syntax is impossible to patch from outside (the "&" operators for label/arguments),
; so macros had been hard-edited to sjasmplus syntax. Other incompatible lines are amended
; through DEFINEs and OPT adjusting sjasmplus parsing

; some defines to change unknown syntax/decorations to nothing or silent assert to ignore them
    DEFINE title assert 1,
    DEFINE aseg
    DEFINE local assert 1,
    DEFINE error assert 0,

ped7g

;-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
; Author: Ped7g ; (C) 2022 ; license: https://opensource.org/licenses/MIT
; Z80N (ZX Next) assembly, sjasmplus syntax: https://github.com/z00m128/sjasmplus
;
; code-size optimisation based on facebook post with small example showcasing the usage of routines
;
; default config of example is doing the counter-clockwise rotation of buffer to screen,
; flip comment to get clock-wise variant:

computeULAFromVRamAddress   EQU     computeULAFromVRamAddressCCW

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

;     DEFINE ORG_ADR $5D01    ; using maximum memory in zx48 snapshot -> prime numbers: 4339, last prime number 41491
;     DEFINE DO_MAX_BUFFER_CASE ; (4339 primes was with shorter test-code, not last version)

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

    OPT --syntax=abf

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
;
; This is second version of the sieve routine (asm-like asm, focusing on performance, hard-wired buffer, etc...)
; For first C-like version check: https://gist.github.com/ped7g/c55bfa0d55ca13ce029549636cdd1de5
;
; sieve routine sieve_a_2 starts around line 110, below test harness

; comment/uncomment the case you wan to debug:

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"