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SpectranetHi all, I just bought a spectranet card and have a couple of questions I hope someone can answer for me. I have played around with it on both a +3 …
... , so the suspicious number is 256, not 512!
My ... read start at the 256th byte.
After a little more ... a read starts on the 256 byte mark (or multiple thereof) it ... -
Relocation with SDCCI desperately need auto- relocation with SDCC. Something that will compile all of my code using start address 0 and generate relocation table so that…
... the two files because low byte of word is equal ... be fixed up to a 256-byte boundary.
Note ... . I write a 12-byte header into the file first ... code itself. The 49-byte relocator then fixes up all ... the places where the high byte doesn't match the ... -
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 …
... the window. Given your constraints, 256 byte window sounds about right. To ... encode the current byte(s), you look back through ... bit 1 followed by the byte itself. This is the key ... even a simplistic version of byte-based LZ77 is likely to ... -
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 …
... ). I could only use a 256-byte buffer as the file is ... size and using a 768-byte buffer compression was 73% and ... -
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 …
... as it only allows a 256-byte window (it does 51% on ... -
Trailblazer - mapped?Anyone mapped Trailblazer yet? I'd kind of like to get hold of the maps. D.
If you:
* create a 256-byte string containing ascending values 0- ... string into the level D byte map at $682D
* select ... -
Fantasy Z80 instructions?This follows on from something catmeows said in another thread, and that I've been meaning to ask for a while. This may sound daft to people with mo…
... setting H=0 and L=256 byte index but you are not ... to just one page of 256 bytes. You're a little ... was no longer a 4-byte "extend" opcode to introduce the ... -
Tape loading - blocks with checksumThese were sometimes used for 128K games and had a searching / loading message, ie. Loading Block 08, then if a block didn't load right one could rew…
... for reliability: 1K packets, or 256 byte packets? - not knowing much about ... -
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 ... you don't need a 256 byte interrupt table as the low ... byte of the interrupt address is ... -
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…
... you don't need a 256 byte interrupt table as the low ... byte of the interrupt address is ... -
Tape loading - blocks with checksumThese were sometimes used for 128K games and had a searching / loading message, ie. Loading Block 08, then if a block didn't load right one could rew…
... in block of up to 256 bytes. If an unrecognised block ... save the screen as 27 256-byte blocks, and load it back ... -
Spectaculator 8 vs REAL diskDoes Spectaculator 8 support real floppy drives? I want to use an external USB floppy drive to read/write +D and +3 floppy disks. I have Windows 7…
... +3, but TR-DOS uses 256 byte sectors and cannot be read ... -
Spectaculator 8 vs REAL diskDoes Spectaculator 8 support real floppy drives? I want to use an external USB floppy drive to read/write +D and +3 floppy disks. I have Windows 7…
... +3, but TR-DOS uses 256 byte sectors and cannot be read ... -
Scrolling by 2 pixelsWhat is the fastest way of scrolling a Spectrum screen line by 2 pixels left or right? When thinking about it I've come to this simple solution: [C…
[QUOTE]Use INC L instead of INC HL.[/QUOTE]
Yes, it could work if we make sure to keep in 256 byte bonduaries. -
Scrolling by 2 pixelsWhat is the fastest way of scrolling a Spectrum screen line by 2 pixels left or right? When thinking about it I've come to this simple solution: [C…
[QUOTE=Ralf;716119]Yes, it could work if we make sure to keep in 256 byte bonduaries.[/QUOTE]
Column coordinates within the Spectrum screen always respect the 256 bytes boundary. -
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. -
Movin And A Groovin Horizontal Flip improvementOn the left is the flip horizontal portion from Andy Pennell'S excellent Movin' & a Groovin' machine code screen routines from Your Spectrum #19 (Oct…
... /> Create lookup table to 256 byte boundary (requires 256 bytes of free space ... />
;17 bytes
256 byte table will look like this ... -
Games featuring... relevant bugsThere was a recent improvement to the WoS database in order to classify [URL="http://www.worldofspectrum.org/forums/showthread.php?t=34261"]Games fea…
...
Checksums reside in 256 byte 1st block.
Patch ... -
Experimenting with turboloadersHello, My first post, having lurked here for a while. I'm a lifelong computer nerd, Spectrum fan since childhood in the eighties, and have recently…
... of a screenful (so, a 256-byte block?) of wrong attributes, then ... -
display file addressing; screen slicingWhile working on this Compendium I'm updating or rewriting a lot of stuff. One thing I eventually came to appreciate was the simple & clever way in w…
... so will fit in a 256 byte page. i.e. you ... L, and read a two-byte screen address out of the ... all the entries within a 256 byte page.
If ... the high bytes in one 256-byte page and the low bytes ... byte, e.g. LD E,(HL).
But that allows 256 ... -
Assembly - Loops bigger than 255Hi, It looks like it's a bit difficult to make loops with more than 255 cycles on Z80 machine code, since the 16-bit decrements (DEC) do not alter a…
... 't sit just before a 256-byte boundary. Then it definitely wouldn ... work (unless by chance, byte_to_write+256 contained the same byte). -
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…
Documentation for SP1 for Z88DK?(I was going to post in [URL="http://www.worldofspectrum.org/forums/showthread.php?t=11729"]the other thread[/URL], so if a mod thinks this should go…
... needs to start on a 256-byte page, which means the ... least significant byte of the address has ... table must start on a 256-byte page (LSB=0) and ... all the same byte. If that byte is in hex ... br /> This 257-byte table containing the same byte has to be ...How to print logo onto screen at chosen coordinates?Hi, I've just got back into zx spectrum games after all these years and after seeing some of the great games on here I would like to start learning p…
... reason that CHARS points to 256 below the character set is ... is why it's a 256 byte offset (32 * 8 ).
256 which is obviously not correct ...Is ESXDOS flexible enough to incorporate e.g. Spectranet commands?I was just discussing the idea with someone about the wish some people have to be able to combine interfaces such as DivIDE (Plus) / DivMMC EnJOY! wi…
... qualified read by reading one byte at a time from ... = void *buffer_ptr (address past last byte written)
; bc = remaining ... eg, which I think have 256 byte sectors; you could always do ... if it can do 256/512/1024 byte blocks efficiently.
< ...Multiply by 48Is there a 'cheat' to multiply by 48 in Z80? I have a table of sprites 48 bytes each entry, and I want to be able to offset my pointer with a simpl…
... memory, put the sprites at 256 byte boundaries and just add the ... base address in the hi-byte of the address pointer register ...Multiply by 48Is there a 'cheat' to multiply by 48 in Z80? I have a table of sprites 48 bytes each entry, and I want to be able to offset my pointer with a simpl…
... . in L directly saving 1 byte. Also, if the base address ... in DE is at a 256 byte boundary (i.e. E=$00 ... we can save
another byte with ld H,E.Multiply by 48Is there a 'cheat' to multiply by 48 in Z80? I have a table of sprites 48 bytes each entry, and I want to be able to offset my pointer with a simpl…
... memory, put the sprites at 256 byte boundaries and just add the ... base address in the hi-byte of the address pointer register ... ;192 which is still a byte)[/QUOTE]
One aspect ... counter cannot jump in 48 byte segments. (good idea still tho ...
