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hash function permutation tableI'm using a simple Pearson hash function to generate keys for a $(103,6) array using a 256-byte permutation table. How do I arrange the entries in th…
... ,6) array using a 256-byte permutation table. How do I arrange the ... entries in the permutation table to avoid any collisions? As ... all the data table entries are known in advance ... of them in 256 numbers so trial & error isn't a ... -
zxasm.net facebook group - COMPO #6 – 256 byte game compo – THE RESULTS !!!The results of the last compo are in. All entries include the source code. [img]http://zx-speccy.co.uk/Copy2WebServerData/2016716_12380.png[/img]…
... /2016/07/16/compo-6-256-byte-game-compo-the-results/"]zxasm ... /2016/07/16/compo-6-256-byte-game-compo-the-results/[/url ... -
Mode 2 Tile Editor SourceA Timex Mode 2 Tile Editor incorporating a byte mirror table. The compiled version is available in the CSSCGC 2008 collection from the WoS archive. …
... 2 Tile Editor incorporating a byte mirror table. The compiled version is ... /> ; ------------
; MIRROR TABLE
; ------------
;
; A 256 byte lookup table to mirror the ... bitmap contained in a single byte< ... -
Head over Heels on the C64Dunno if this' a good place to bring this up :D I've been comparing Head over Heels versions and the C64 version is way inferior, everytime there's…
... only speeded up using a 256 Byte LookUp table. I know it because ... to figure out the correct table contents (Thanks to Wilko Schr ... all games use such a table? -
Head over Heels on the C64Dunno if this' a good place to bring this up :D I've been comparing Head over Heels versions and the C64 version is way inferior, everytime there's…
... only speeded up using a 256 Byte LookUp table. I know it because ... to figure out the correct table contents (Thanks to Wilko Schr ... all games use such a table?[/QUOTE]
By and ... more messy, but a lookup table can be used to make ... -
Please test my Manic Miner remake!Thanks to everyone who downloaded my sneak preview of Manic Miner Turbo. Thanks especially to na_th_an who is the only person so far to give feedback…
... .5K shift right & left table for that (or a 1 ... .75K rotate table and mask it to get ... some memory by using a 256 byte mirror table (or generating one as ... -
Cool BASIC tricks and tips!Following on from Dunny's excellent suggestion of a compendium of BASIC tips + tricks, I believe it would be better to have a topic dedicated to it. …
... speed, you have to use 256-byte aligned table. -
Sprites masterclassHi All, You guys are probably tired of explaining sprites but I'd like to clarify a few things if possible. I've sorted the vertical aspect of scro…
... for the movement and a 256 byte mirror table, the second set of ... -
Fastest way to mirror a byte?I.E. turning 01100000 into 00000110, in assembly. I'm trying but I suck at stuff with rotation and the carry bit. Any pointers?
If anyone wants to be really smart, come up with a PASMO Macro that generates a 256-byte mirror table.
I can imagine resorting to Excel for that, myself. -
Fastest way to mirror a byte?I.E. turning 01100000 into 00000110, in assembly. I'm trying but I suck at stuff with rotation and the carry bit. Any pointers?
... PASMO Macro that generates a 256-byte mirror table.[/QUOTE]
I can ... right place:[code]
REPT 256, x
defb ((x> ... -
Fastest way to mirror a byte?I.E. turning 01100000 into 00000110, in assembly. I'm trying but I suck at stuff with rotation and the carry bit. Any pointers?
... hl,&4000 ; first display byte
ld de,&57ff ... ; last display byte
ld b,revtab/256
loop:
halt
defs (-$)%256 ; 256-byte align
revtab:
defb & ... -
Where do you stick the stack?...OK, so I've got a fair chunk of ASM code assembled from 24000 mark. The stack shouldn't get very big, just a few PUSHes and POPs of the main regis…
... SP,$5BFF and use the 256 bytes in the unused area ... Jetset Willy use every single byte of the 48K including System ... 't need a 256 byte interrupt table as the low byte of the interrupt ... -
Where do you stick the stack?...OK, so I've got a fair chunk of ASM code assembled from 24000 mark. The stack shouldn't get very big, just a few PUSHes and POPs of the main regis…
... 't need a 256 byte interrupt table as the low byte of the interrupt ... -
Mirroring UDG'sJust wondered is there a quick an easy way of mirroring UDGs (byte values)? i.e. BIN 11110000 becoming 00001111 etc.
The quickest way is to use a pre-calculated 256-byte flip table aligned to a page boundary, like the one at [url="http://pyskool.ca/disassemblies/contact_sam_cruise/asm/32256.html"]32256[/url] in Contact Sam Cruise. -
hash function permutation tableI'm using a simple Pearson hash function to generate keys for a $(103,6) array using a 256-byte permutation table. How do I arrange the entries in th…
A 256 byte hash table seems ideal for implementation in ... emulators already use a hash table to decode the opcodes (Zero ... optimize it to a jump table I've been told), but ... -
I'm writing an Operating SystemOkay this might seem like a bait thread, but I am legitamately interested in figuring out how to write a multi-process system for the ZX Spectrum (no…
... you elaborate on the 256-byte alingment you talk about ... 256-byte boundary?[/quote]
If someone has created a 256-byte aligned table ... it assuming it's 256-byte aligned then you can ... generate code dependent on 256-byte aligned data structures so ... -
Tricks to make mirror image of a graphic?I've been working on a sprite routine for lots of sprites and animations. I'm only storing right facing graphics, and converting them to left facing.…
... ]
Testing if the byte is $ff or $00 and ... 333.
Using the 256 byte mirror table takes 333 T-States for ... -
How to disable the "scroll?" message?Hello. I'm a beginner Z80 assembly programmer and I decided to make a ZX Spectrum game to practice my skills and gain some more experience. I curr…
... tbl_scraddr be aligned to a 256 byte boundary
adc h ... tbl_scraddr be aligned to a 256 byte boundary
adc h ... br /> ALIGN 256
; screen address table. This must be 256 byte aligned
Error checking is non-existent ... -
Console frameworkStill working on Specotron, but at the point where working out the diagonal lines collision is not good at beer o'clock. In the meantime I've knoc…
... (hl) ; first byte of value in table
inc l
byte of table
add d ; add on ... ld h, (hl) ; second byte of table
add d ; add on ... 00 ; `
ENDIF
ALIGN 256
tbl_rows dw SCRBUF_BASEADDR + #0000 ... -
Console frameworkStill working on Specotron, but at the point where working out the diagonal lines collision is not good at beer o'clock. In the meantime I've knoc…
... (hl) ; first byte of value in table
inc l
byte of table
add d ; add on ... ld h, (hl) ; second byte of table
add d ; add on ... 00 ; `
ENDIF
ALIGN 256
tbl_rows dw SCRBUF_BASEADDR + #0000 ... -
Console frameworkStill working on Specotron, but at the point where working out the diagonal lines collision is not good at beer o'clock. In the meantime I've knoc…
... /> ELSE
FONTBASE EQU nice_font - 256
ENDIF
DBG_REST_OF_IBUFF ... h, tbl_rows/256 ; address of the screen rows table page
; add ... /> ld h, (hl) ; second byte of table
add d ; add on ... -
Console frameworkStill working on Specotron, but at the point where working out the diagonal lines collision is not good at beer o'clock. In the meantime I've knoc…
... /> ELSE
FONTBASE EQU nice_font - 256
ENDIF
DBG_REST_OF_IBUFF ... h, tbl_rows/256 ; address of the screen rows table page
; add ... /> ld h, (hl) ; second byte of table
add d ; add on ... -
Console frameworkStill working on Specotron, but at the point where working out the diagonal lines collision is not good at beer o'clock. In the meantime I've knoc…
... /> ld h, (hl) ; second byte of table
add d ; add on ... />
; aligned data first
ALIGN 256
alignedsectionstart:
IF !USEROMFONT ... size: ", 0
str_error db "ERROR: ", 0
str_err_unterminated_literal db " ... -
Console frameworkStill working on Specotron, but at the point where working out the diagonal lines collision is not good at beer o'clock. In the meantime I've knoc…
... h, (hl) ; second byte of table
add d ; add ... h, (hl) ; second byte of table
add d ; add ... `
ENDIF
ALIGN 256
tbl_rows dw SCRBUF_BASEADDR + #0000 ... ", 0
str_error db "ERROR: ", 0
str_err_too_few_args db ... -
Console frameworkStill working on Specotron, but at the point where working out the diagonal lines collision is not good at beer o'clock. In the meantime I've knoc…
... h, (hl) ; second byte of table
add d ; ... h, (hl) ; second byte of table
add d ; ... br /> ENDIF
ALIGN 256
tbl_rows dw SCRBUF_BASEADDR + #0000 ... /> str_error db "ERROR: " ; use first byte of key_tbl_symshift as terminator ... -
Console frameworkStill working on Specotron, but at the point where working out the diagonal lines collision is not good at beer o'clock. In the meantime I've knoc…
... was not found in intrinscis table
; otherwise DE has ... />
; aligned data first
ALIGN 256
alignedsectionstart:
IF !USEROMFONT ... : ", 0
str_error db "ERROR: " ; use first byte of key_tbl_symshift as terminator ... -
Console frameworkStill working on Specotron, but at the point where working out the diagonal lines collision is not good at beer o'clock. In the meantime I've knoc…
... was not found in intrinscis table
; otherwise DE has ... />
; aligned data first
ALIGN 256
alignedsectionstart:
IF !USEROMFONT ... : ", 0
str_error db "ERROR: " ; use first byte of key_tbl_symshift as terminator ... -
A sped up pixel-shift routine for 1-byte–wide spritesHere’s an optimized (for speed) real-time sprite shifting routine for sprites that are one byte wide. It uses no memory variables for storage of inte…
...
[code] align hi($)==hi($+8) ? 1 : 256[/code]
256-byte boundary. If that’s not ... /> inc l ;advance to next byte (make sure sprite data is ... ;else, load A with high byte of screen address
sub ...
