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SPIN's breakpoints - an overviewAs quite a few people have been asking how to set breakpoints on memory write etc. in SPIN, here's a description of the way the breakpoints work. Get…
... /> That would break when the byte at 23672 = 3. Square brackets ... , [hl] would read the byte at HL (at the time ... would break as soon as a byte of more than 127 is ... the so-called "high" byte of the address onto the ... to care about the high byte of the address at ... -
How does the Z80 work internaly?How does the Z80 work internaly, i.e. how does it actually execute a machine code instruction? When it fetches a byte from the memory and finds, for…
... ?
When it fetches a byte from the memory and finds ... mean the instruction "[B]INC A[/B]", how does the CPU ... at a low level know what to ... -
problem using FRAMES to generate 'random' numbersI realise the pros use bytes from ROM to get their random numbers, presumably because they want to use FRAMES to synchronise the printing and avoid s…
... bit of FRAMES (least significant byte) and using the last ... that direction. This produced a very satisfying irregular zigzag until ... got a better idea for a fix without resorting to calling a byte ... from ROM?
here's a snapshot:< ... -
Scumdog Millionaire.Very clever film. What bugs me is that it utilises the global popularity of the quiz show "Who Whants To Be A Millionaire" to familiarise its audien…
... /> "Who Whants To Be A Millionaire" to familiarise its audience ... the "Who Whants To Be A Millionaire"
format and ... contestant had to correctly answer a million
questions in ... LINES' left - 'Random', 'Flip A Coin' and 'Say A Prayer'."
... -
Help needed to convert TZX/CDT format to buffered dataHi together, I registered today because I could need some help from ZX-Spectrum emu-coders. I am developing an Amstrad CPC emulator in JAVA, which …
... , where I convert a WAV file into a byte array and this is ... a JAVA routine, which converts a TZX/CDT file into the same byte ... how I write and read a WAV file... -
So what about ethernet and ZX BASIC?Well, as of about 5 minutes ago, ZX BASIC for the first time properly wrote some packets to the network! OK, so it isn't perhaps 100% what Andrew Ow…
... number. INPUT #, INKEY$# (to poll a socket stream), PRINT #, LIST # ...
Spectrum streams work a byte at a time, which would be horrifically ... the network (a whole packet just for each byte!) and ... each stream has a 256 byte buffer in a page of Spectranet ... -
Wrong-endian data table?I'm drawing up the memory map for something I'm writing. I'll be using machine code on a byte array of 256 elements, each element consisting of 64 by…
... be using machine code on a byte array of 256 elements, ... the LSB and the byte offset in the MSB. ... be selected with a single [b]LD L, A[/b] instruction ... This would be a bad idea on a modern computer: deliberately ... cache. Not an issue with a ZX Spectrum.
Nibble SwapHi, I want to swap around the nibbles in a byte pointed to by the IX reg, this works: [CODE] LD A,(IX+5) AND %11110000 RRA …
... around the nibbles in a byte pointed to by ... /> [CODE]
LD A,(IX+5)
AND %11110000 ... H ; combine a with h
; a = nibble swapped byte
[/ ... CODE]
Is there a more ...fast font engine possible?inspired by the recent "proportional font" thread for zx basic and ideas for gui and having done some of the work on this in the past i wonder if it …
... … first ascii = 'A'
byte 1: 65 … last ascii = 'A'
byte 2: 0 ... … proportional font
byte 3: 10 ... format)
byte 7,8: mask for a 1111111111111000
byte 9,10 ...+3 Copy ProtectionHi all, I've been looking at copy protection and I've realised that, as a kid, I thought things like speedlock were there to stop you poking the gam…
... 've realised that, as a kid, I thought things ... commercial disk but readable on a copy - was this the ... you couldn't just do a byte for byte disk image?
...
My knowledge of disks is a ... systems? (In which case a bit for bit copy ...Keys redefine routine and key check.I have written some asm code which allows me to redefine keys (for a game etc.), and also allows me to be able to check any keypresses for the redefi…
... check bits in a byte (cos I haven't a clue lol)
out (254),a
ld a,4 ; black paper, green ... the key_xxx_pattern byte
ld (hl),a ; save the pattern byte
... back to the key_xxx_port byte
ld a,(de) ; get the ...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?
I.E. turning 01100000 into 00000110, in assembly. I'm trying but I suck at stuff with rotation and the carry bit. Any pointers?washing machinesdoes anyone else have trouble with them. my gf has been whinging that i dont do enough round the house, so i thought id wash the bed sheets. there…
... .
there are like a million settings on the thing ... figure out i had to flip a socket switch near the kettle ...appending data while saving to tapeBefore trying to do this I just wanted to check if there's a possibility that it might actually work. I have a number of string arrays which I want t…
... to check if there's a possibility that it might ... actually work. I have a number of string arrays which ... I was wondering if using a modified version of SA- ... DE. There would be a short time at each break ... would normally have been saving a byte, but it's altering ...Screens and BasicA question about the ZX screens. I am using software to convert my own art and drawings to the ZX Spectrum. I have some tools to change .jpg files in…
A question about the ZX screens.< ... into an emulator or into a real ZX?
I mean ... .tap files the speccy finds a "Bytes: so and so" and ... in BASIC to load such a "byte" file?LZ4 decoderI encountered the [URL="http://code.google.com/p/lz4/"]LZ4 compressor[/URL] a few weeks ago. Reading the [URL="http://fastcompression.blogspot.co.uk…
... rra
ld c,a ; copy into byte counter
cp 15 ... length
ld c,a ; save in byte counter
... .getlength:
ld a,c ; read low byte of byte counter (4T)
Assembly code auto optimiserFor my Finders Keepers Plus project I'm considering writing an Assembly code auto optimiser. Way back when I wrote the original FK I considered optim…
... do this would have saved a byte every time and sometimes ... two.
A pre-processor could also search ... but it may be a case of loads of work ... for a very minimal saving. And ... fill that much memory with a game!? :)
...Using even ports for input?I've been looking for unused ports to use with my clashbasher interface. I understand that the spectrum only considers A0 when decoding its input p…
... with resistors. And the high byte of the address bus is ... why not set the high byte to FF so the ... in the cpld which outputs a byte from a eight bit counter to ... used for loading and having a tape playing at full ... s only used on a spectrum with a floating bus it ...From RAM to dim v$() "video buffer" SPEED UP!Hi! This question is related to "quick RAM copy using LET in Basic" ([url]http://www.worldofspectrum.org/forums/showthread.php?t=44296[/url]). Wel…
... make a bucle from 0 to 159 bytes for read a byte.
- If this byte readed from RAMPEEK ... +1,byte
POKE dir+32,byte
POKE dir+33,byte[/INDENT ... $(pos to pos+1)=chr$(byte)... but takes same time...:confused ...PC to +3 communicationsHi I'm going to explore the abilities of my +3 to communicate with a PC. The "natural" ways to do that would be via serial or parallel link. I've b…
... my +3 to communicate with a PC. The "natural" ways ... communication (timings, grouping bits into a byte, those things) or everything ... only, and there is only a input bit (BUSY). Is ... ? Can I only get a bit from the outside?
a +3 RS232 to DB9 ...FUSE serial communication sample anyone?Hi, in [URL="http://manpages.ubuntu.com/manpages/precise/man1/fuse.1.html"]FUSE man pages[/URL] one finds switches for serial comms. By using --inte…
... ."
Does anyone have a sample on the PC side ... being handled as common files? A Unix GNU C sample on ... side that sends and receives a byte to and from fuse program ... research & test phase; while a sample on both sides (PC ...Pixel level collision detection[SIZE=3][FONT=Calibri]I need to do some pixel level collision detection. Assuming I have a byte of my ?player? sprite in DE and a byte of screen to t…
... collision detection. Assuming I have a byte of my ?player? sprite ... in DE and a byte of screen to test in ... [CODE]
ld a, (de)
ld b, a
xor (hl ... this would work. Is there a better / faster way to ... I know the player and a ?bad? tile are ...Execution map file support in different emulatorsAs I'm now seeking about execution map files, the different emulators support, I want to start a new discussion here. Today, I tried to create a mem…
... , I want to start a new discussion here.
... where each bit represents a byte of the 64 k memory ... 65536 bytes, where each byte calculates the code or data ... /> bit 1: =1 means byte reading
bit 2: = ... /> bit 3: =1 means byte writing
bit 4: = ...I feel they could have done this.After reading the ZX Spectrum ULA, I learned about how the ULA detects if the Z80 if going to access memory in the next cycle and stops it if the ULA…
... think they could have made a superior computer. I think the ... an address and a byte, and the byte gets held in a buffer until ... no expert but I think a slightly different arrangement could have ... resulted in a much faster computer with a little more usable ...Mirror tableCan anyone help with a byte mirror table? e.g. so you can look up a byte of a left-facing sprite and return the correct right-facing value. There …
... a byte mirror table? e.g. so you can look up a byte of a ... />
There was a discussion about it a while ago, but I ... way of looking up a byte and returning its mirrored value ... /> Also if anyone's got a byte mirror table to hand, please ...The history of ESXDOS, the DivMMC and the DivMMC EnJOY![img]http://benophetinternet.nl/hobby/divmmc_history/1%20esxdos.jpg[/img] These are the stories behind esxDOS, the most popular operating system e…
...
This project was a collaboration between Miguel and LaesQ ... continues again:
[i] “A couple of months earlier Alessandro ... />
esxDOS is a modular operating system, which means ... CPLD.
Transferring a byte to/from the card requires ...Chompston Mazes in SpecBASAfter the discussion in ASH-II's Pacman thread, I checked out the link there about generating 2D Pacman style mazes. This one was quite good fun, …
... [/url] which is a lovely little pacman/bomberman ... Now we define a function - which returns a number between ... e$(a),e$=e$( TO a-1)+e$(a+1 TO ... CHR$ to convert from a number to a byte value.
a usable form.
The Olympic Mega Thread.So anyone watching the Olympics opening ceremony tonight? I am disappointed Pele will not be lighting the Olympic flame. I wold have loved to see him…
... see him kick or back flip a fireball in to the air ... could be in line for a medal tally in the early ... bet the Olympics will deliver a fair few world records as ...Proportional fontsI've been doing some proportional font drawing, purely on C level at the moment, but it's orders of magnitude slower than I'd want it to be. It's sti…
... 8 bytes each (plus a byte for width), aligned to ... we move to the next byte, shift the mask backwards ... the time. I did a couple variations of the ... scanline, handling one character at a time.
[ ... faster. The char-at-a-time version is more pleasing ...
