-
my tiny intros[IMG]http://pouet.net/screenshots/60493.png[/IMG] [url]http://pouet.net/prod.php?which=60493[/url] the following work will appear behind Demosplash…
... /> algorithm is similar - the index register IX are using to access color ... hl, # 5800, the value of register L is not important, in ... /> ld e, (hl); refused to register D = 0
inc l ... - I think that the command register USR A = 0
after ... -
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…
... deal with the stack (SP register) and restore it to the ... itself up, use LD a, (IX+n) to load in (8 ... parameter already in the A register for free when the routine ... -
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…
... itself up, use LD a, (IX+n) to load in (8 ... parameter already in the A register for free when the routine ... c,a
ld a,(ix+7)
cp 28
ld a,(ix+9)
add hl,hl ... -
SCF/CCF flags - new discoveryI can't believe that no one is interested in discussing the additional, previously undocumented internal state of the Z80 CPU I have discovered recen…
... sure there's another internal register (or just a flip-flop ... the case of instruction or IX/IY prefixes). Or an incomplete ... of how this WZ (MEMPTR) register is used. :???: -
ZX Spectrum Core EmulatorHi All, Here i have my ZX80 Core Emulator. Which im working on to help me complete the Spectrum PLAYBASIC Emulator. I hope this comes in use for o…
The I register is not related to the index registers. i.e. IX is not a register pair made from I and X, it's simply the 16 bit register IX. I is the interrupt register. -
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 …
... some bytes more (for the register storage) at the end of ... , instead:
[CODE] ld ix, source
ld de, length ... -
pathfindingworking on pathfinding in the game. here is Russian description of Lee's algorithm: [url]http://algolist.manual.ru/games/wavealg.php[/url] "if-then"…
... area of 256 bytes, with register HL pointing to first element ... actual algorithm implementation requires using IX/IY instead of HL/DE ... -
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…
... -based addressing, but the ix-based addressing is close enough ... It's unfortunate that every ix/iy access pays an additional ... 705409]sdcc uses the index register approach that makes it easy ... used variables are referenced using ix, and more frequently accessed ... -
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…
... />
Register relative indexed addressing as in "LD r,(IX+r)" in ... addition to "LD r,(IX+n)" would be nice. Add ... the lot ran faster. Using IX, eg, no longer had a ... -
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…
... used variables are referenced using ix, and more frequently accessed ones ... block level I have a register interface to the function. In ... -
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…
... like address mode flags, which register you are operating on, etc ... more efficient.
The IX and IY registers should be ... instructions.
The ALU, IX/IY and prefetch shouldn't ... -
20-column multicolour: a half-baked ideaI was writing an email reply to one Mr Jowett about multicolour routines, and in that way that explaining something to someone else makes you think "…
... to load initial values into register pairs AF,BC,DE,HL ... ,AF',BC',DE',HL',IX,IY and to set SP ... -
Full 16*16-digit BASIC multiplicationI liked Andre Adrian's 32-bit long multiplication routine so much that I decided to a decimal version. After all, 2^63 is only 9223372036854775808, a…
...
pop hl ;HL=register pointer
ld (hl), ... initial register values are in WORKSP.
di
ld ix, ... /> push hl ;save decimal register address
ld de,PADDATA ... -
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…
... to load) and L (the register in which the bits decoded ... replaces the INC IX at 8645 with DEC IX, one gets a ... LD (8646),A
LD IX,22507
LD DE,6144 ... LD (8646),A
LD IX,22508
LD DE,768 ... and loading new values into IX and DE works perfectly well ... -
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…
... :equ 256-.one_pulse_max
;; REGISTER ALLOCATION
;;
;; B ... ; store byte
inc ix ; advance pointer
dec ... a screen
ld ix,16384
ld de ... -
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…
... :equ 256-.one_pulse_max
;; REGISTER ALLOCATION
;;
;; B ... 's counter
;; IX:target address of next byte ... ; store byte
inc ix ; advance pointer
dec ... -
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…
... :equ .one_pulse_min+.timing_constant_data
;; REGISTER ALLOCATION
;;
;; B: .read_edge ... loader_advance_pointer
else
inc ix ; advance pointer
endif
Can a guy that traveled on the short bus learn machine code...Hmmm So after some soul searching I figured it was time to finaly nail spectrum machine code. Its so frustrating to sit infront of a basic listing w…
... br /> DD19 = ADD IX,DE
DD29 = ADD IX,IX
DD39 = ... ADD IX,SP
DD84 = ...
DD86 = ADD A,(IX+*)
FD09 = ADD IY, ... load 3E00 instead.
REGISTER A
[code]< ...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…
... each line flip. The stack register (SP) is used, but has ... hl,$5AF0
ld ix,$0000
add ix,sp
ld ... nz,lp3
ld sp,ix
ret
54 ...Can a guy that traveled on the short bus learn machine code...Hmmm So after some soul searching I figured it was time to finaly nail spectrum machine code. Its so frustrating to sit infront of a basic listing w…
... tight loop might use one register set, the loop around that ... to the device driver (in IX, eg) and will set up ... calling the device driver through IX allows the function dispatcher to ...Can a guy that traveled on the short bus learn machine code...Hmmm So after some soul searching I figured it was time to finaly nail spectrum machine code. Its so frustrating to sit infront of a basic listing w…
... , WZ is that IX or IY or a tempoary register???? he is ... value before frotteurism of the register could it even be done ...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…
... extra 16 bit register is needed without resorting to IX or IY ... , and without the need to manipulate its individual register ...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 …
... a trip to the A register ("sbc a,a; and ... int
; bc = radix
; ix = char *
; stack = char * ... to string
; ix = char * (current write location)
push ix
call asm_utoa
pop ...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 …
... a trip to the A register ("sbc a,a; and 0x01 ... /> 2) push af: bit 0, (ix-n) to test.
3 ...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 …
... 2) push af: bit 0, (ix-n) to test.
3 ... so slow. That "bit 0,(ix+d)" is 20 cycles. ... first parameter in register xx, the second in register yy, etc ... pointers and a single register parameter might need a ... 38 cycles for using IX to access a single ...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 …
... function pointers and a single register parameter might need a think ... ) is compatible with zcc, as ix is saved, then the new ... is recalculated from sp, not ix. The bad news is that ...What would be the simplest tape loading routine?I'm searching for some small assembly snippet I can use to load a (headerless or not) block from tape into RAM I can embed in my C games to load furt…
... tape.
LD (IX+00),L Make the actual ... /> 05C2 LD-NEXT INC IX Increase the 'destination'.
... in the L
register.
LD B,+ ...Manic Miner ZX81Hi Guys, Can anyone explain why [url=http://www.worldofspectrum.org/infoseekid.cgi?id=0017539]Manic Miner ZX81[/url] is not able to reproduce the ex…
... many games.
By changing IX to your own routine you ... out by setting I-register and R-register and a call to ...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…
... it
call fp_to_a ; get register byte
cp 17 ; check ... a ; to BC
ld ix, be_ix_plus_3 ; base loop
add ... l ; reset C
jp (ix) ; back to loop offset
jp (ix) ; jump back
...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…
... /> ;proper copy routine
LD IX,49152 ;source start is 49152 ... /> REPT 18
LD SP,IX
POP HL
POP ... /> LD DE,60942
ADD IX,DE
ADD IY,DE ... done as they destroyed flag register which is used in POP ...
