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BIFROST* ENGINE 1.2 released!Another improved version of the BIFROST* ENGINE is now available! Download it here: [url]http://www.worldofspectrum.org/infoseekid.cgi?id=0027405[/u…
... a moveable buffer pointer, and 28-wide if I really push the ... copying from a linear buffer. Using LD/PUSH it might even be ... -
64x48 full colour graphicsHow feasible is this? Could an interrupt-driven routine be used to, for example, fill the top two thirds with a 64x32 blocky picture and leave the bo…
... changing SP and doing a PUSH. You can also use it ... fetch the data from a buffer.
One line takes ... problem is the fastest operations (PUSH) fill right-to-left when ... -
64x48 full colour graphicsHow feasible is this? Could an interrupt-driven routine be used to, for example, fill the top two thirds with a 64x32 blocky picture and leave the bo…
... />
PUSH IY ;copy MV11
PUSH IX ;copy MV10 ...
PUSH AF ;copy MV9 ...
PUSH BC ;copy MV8 ... br /> LD HL,(CurrentLineAttrs) ;next buffer data
ADD HL,DE ... -
16k Issue 2 board and DivIDE load errorsI today got an Issue 2 16k board (thank you PMSR) that i added the logic and ram on to get a 48k machine. However, I am unable to load software from …
... used to have just a buffer transistor. But this was not ... are a bit easier to push. Then I hooked up a ... -
copying between RAM pagesSay I'm storing stuff in RAM pages 0,1,3,4 which gets used in 6,7 (which I am) and I might want to transfer up to 7kb at a time (which I do) and I do…
... to make doing it via PUSH/POP worthwhile given how many ... maths!). I think an intermediate buffer and multiple copies is probably ... -
What Spectrum projects (Software/Games/Utility)(Hardware)(Others) are you working on?So, basically that :) You dont have to give names or more clues if you dont want to ;) Also, if you are working on more than one, you can tell all of…
... [/B] having a go at PUSH scrolling. Don't forget that ... does rl (hl) on a buffer consisting only of 'char cell ... one can rotate the tiny buffer very quickly (it's the ... screen behind the scanline. The PUSH routine can also be looped ... -
Asking for help: ZXBC to ASM routine translationHallo, In order to save some bytes and gain speed, I'm asking for translation of a very simple ZXBC routine to Assembler [code] sub light(x as uinteg…
... intensity? - assuming a
push hl ;push return address back
ld de,@buffer
add hl,de
ZX7: an "optimal" LZ77 packerAbout 20 years ago, I started a M.Sc. in Computing, planning to work on data compression. Although I quickly changed to another subject for a number …
... -reverse without using a temporary buffer.[/quote]
So with ... the screen without a temporary buffer. And this will enable a ... ; store source, restore destination
push hl ; store destination
sbc ...ZX7: an "optimal" LZ77 packerAbout 20 years ago, I started a M.Sc. in Computing, planning to work on data compression. Although I quickly changed to another subject for a number …
... ld de,$c000
push de
call dzx7
next_row:
push de
call $0E9B ; ... works with any intermediate buffer (the buffer address doesn't ... ld de,rcs_buffer
push de
call dzx7
ZX7: an "optimal" LZ77 packerAbout 20 years ago, I started a M.Sc. in Computing, planning to work on data compression. Although I quickly changed to another subject for a number …
... :
[CODE]; from RCS buffer to screen (DE must contain ...
ld de,rcs_buffer
push de
call dzx7
RCS (Reverse Computer Screen)[B]RCS[/B] ("Reverse Computer Screen", or simply SCR written backwards) is a small utility I'm about to release, that reorders bytes from the ZX-Spec…
So how do you use RCS in practice? It's quite simple:
[LIST]
[*]First transform a regular ZX-Spectrum screen file (such as "Cobra.scr") into the RCS format (producing "Cobra.scr.rcs") using the command-line utility RCS;
[*] ...RCS (Reverse Computer Screen)[B]RCS[/B] ("Reverse Computer Screen", or simply SCR written backwards) is a small utility I'm about to release, that reorders bytes from the ZX-Spec…
... />
; Preserve initial address
push de
; First step ... above would require a temporary buffer of 64 bytes: for each ... ordered as "r2r3p1p2p3r1" to this buffer, then copy them again to ...Bottom 4 lines of the screen fileI'm wanting to save the bottom 4 lines of the display memory (AT 20,0 to #0; AT 1,31) 23168 is the start of the attributes and its length will be 32…
... /> CALL GETPRADDR
PUSH HL
LD DE, ... 32
SPRSLP2 PUSH BC
PUSH HL
LD ... /> CALL GETPRADDR
PUSH HL
LD DE ... 32
RPRSLP5 PUSH BC
PUSH HL
LD ... 1024,$00 ; 1024 byte buffer for screen save
...Keyboard TrickI know how to use the multi key in BASIC with IN you can get the keys [QUOTE]IN 254+256*(255-2^K)[/QUOTE] K is the keyboard's half row, comes from …
... HL, result
PUSH HL ; Will return buffer position later
LD ... to where you want the buffer to be.
;22528 ... address of the 40-byte buffer)
[/code]
... a slightly longer routine, the buffer could order the keys in ...Disabling the +3 disk buffer; yes, but how?I would like to disable the +3 disk buffer in order to retrieve those 4K from the machine's RAMdisk. By reading the computer manual and some posts on…
... will disable the +3 disk buffer. This hardly makes any difference ... once, and a cache or buffer doesnt make hardly any difference ...
LD BC,32765
PUSH BC
DI
LD ...Emulator audio...how?Hi all. I am in the process of writing a Spectrum emulator (c#) for my final year project at university. I've got it all working, apart from sound. …
... value accordingly). Push this sound value to the sound buffer.
buffer. You will need a few ... waiting for the current sound buffer to finish playing 882 samples ...Z80 internal compressionThis isn't exactly a ZX Spectrum problem, but since WOS probably has some of the best Z80 coders in the world, I thought I might ask anyway. For my …
... NC,UM6 ; be
PUSH BC
PUSH HL
LD L ... displacement in the already decompressed buffer is read from the input ...
DEC HL
PUSH BC
PUSH HL
LD L ...Some thoughs about fast scrolling on 128 modelPlease, consider this article as technically interesting concept not a proven algorithm. ONE The fastest scrollers use long sequence of PUSH inst…
[QUOTE=joefish;707054]Also a PUSH takes 11 cycles, or 16 ... each PUSH is highly conservative. In my experience with double screen buffer ...AGD and CGD....can we have a compromise?Well I have been using Jonathan Cauldwell's Arcade Game Designer and I started to look at Dave Hughes' Classic Game Designer. I must say that they ar…
... constant-pixel-scrolling scenery, or push-character-scrolling, or simple flick ... -scrolling scene held in a buffer with a character-by-character ...Compiler conventions for passing args/return valuesI've been mulling over this for a while, but I can't spot it covered anywhere. There are various methods for passing args and return values between …
... ,(_score)
push hl
ld hl,buffer
push hl
ld ... hl,10
push hl
push hl
ld hl,buffer
push hl
ld ... ,10
push hl
ld hl,buffer
push hl
ld ...Machine code optimisationI'm geting back into z80 coding and wonder what the best way of showing how efficient the code is. I've got Rodney Zaks book and see there are timin…
... to use Joffa's LD/PUSH method to get graphics data ... 't bother using a back-buffer). One efficiency to keep in ...Compiler conventions for passing args/return valuesI've been mulling over this for a while, but I can't spot it covered anywhere. There are various methods for passing args and return values between …
... :
1) push af: pop af when needed ... in use.
2) push af: bit 0, (ix ... function needs HL, it can push it itself. Either way, ... then it has saved a push (and possibly corresponding pop ... f = utoa;
(f)(score, buffer, 10);
How is ...How much does Bifrost improve graphics (test 192x192 graphics)Inspired by the BIFROST library I made several experiments with 8x1 graphics at 192x192 resolution. The results are now overwhelming but under certai…
... you're only doing 16 PUSH instructions per line.[/QUOTE]
push limits. Also, it works within single buffer as there ...Copy 4Kb in Assembly?Here's an interesting problem: what's the best way to copy a block of 4Kb in assembly? The most obvious solution is to use [B]LDIR[/B]: [CODE] l…
... memory (for instance copying from buffer to screen) during contention, the ... "rolled loop" sequence of [B]PUSH[/B]es above would have ... possible routine to copy from buffer to screen should probably use ... "rolled loop" routine so [B]PUSH[/B]es are executed during ...Copy 4Kb in Assembly?Here's an interesting problem: what's the best way to copy a block of 4Kb in assembly? The most obvious solution is to use [B]LDIR[/B]: [CODE] l…
... /> LD HL,NN
PUSH HL
LD HL,NN ...
PUSH HL
LD HL,NN ...
PUSH HL
LD HL,NN ...
PUSH HL
LD HL,NN ...
PUSH HL
...[/QUOTE]
... but our data (a screen buffer for example) are a ...Copy 4Kb in Assembly?Here's an interesting problem: what's the best way to copy a block of 4Kb in assembly? The most obvious solution is to use [B]LDIR[/B]: [CODE] l…
... the "rolled loop" [B]PUSH[/B] I listed above would ... , the "rolled loop" [B]PUSH[/B] version could be further ... I wouldn't put a buffer in a contended bank of ... use "rolled loop" [B]PUSH[/B]. And if your program ... of "rolled loop" [B]PUSH[/B] during screen scan such ...SE Basic IV Buffy v4.1 source (WIP)I've been doing a major refactor on the SE Basic source and I'd appreciate a code review from anyone who has time to look at it. I've almost certainl…
... stack
push de ; stack both
push hl ; pointers< ... ; alternate register set
push hl ; stack HL'
... 0x2e1e
pf_save:
push de ; copy
exx ... hl) ; get digit from buffer
inc hl ; next ...SE Basic IV Buffy v4.1 source (WIP)I've been doing a major refactor on the SE Basic source and I'd appreciate a code review from anyone who has time to look at it. I've almost certainl…
... -----------------------------------------------------------------------------
; THE 'SCROLL BUFFER' SUBROUTINE
org 0x2571
s_scrn_str_s_2:
push bc ; stack count
push bc ; stack count
push de ; ...IF EXIST?In MS-DOS scripting, there is an IF EXIST command that lets you check wether a file exists in disk or not. There are any way to check it out from BA…
... The caller passes a buffer pre-loaded with the first ... /> directory entries.
Buffer format:
Entry 0 ... )
DE = Address of buffer (first entry initialised)
HL ... = Number of completed entries in buffer, 0...n.
(If ...
