-
IN 255 behaviour not emulated in Spectaculator and ZXSpinI'm not speaking about "normal" IN 255 behaviour. All of you know what I'm taking about: IN 255 can be used to "read" screen data as it's retrieved f…
... wants to initiate a bus cycle that might affect contended ... the ULA stops the Z80 clock until it has finished. ... bc
call TestInFF
jr nz,NoPrint
pop bc ... -
Vega ARM SOC?I read that the core of the new Vega was an ARM SOC. I thought it would have been an FPGA. But it seems it's an ARM running an emulator. Anyone kn…
... T-state is a CPU clock cycle, about 290ns). 224 T-states ...
or c ;4T
jr nz,WaitUntilScreen ;12/7T
;10 ... -
Z80 cycle contentionHi, Does anybody knows exactly when the ula halts the Z80 clock during a memory r/w cycle? I mean which Z80 clock cycle, T1 or T2? Thanks..
Hi,
Does anybody knows exactly when the ula halts the Z80 clock during a memory r/w cycle?
I mean which Z80 clock cycle, T1 or T2?
Thanks.. -
Pixel Explosion CodeJust a little snippet to cause explosive effects. It uses table lookups for the screen address, and can handle up to 32 pixel particles. A particle…
... )
cp 0
jr nz,lp1
ret
... br /> ld a,32 ; cycle through 32 particles (32x8=256 ... we reached the counter
jr nz,madp_nx2 ; if not, check ... -
Tutorial - learn machine code in 30mins[B][I]Message from the moderators[/I] - bigjon has requested that readers' attention be drawn to a better version of this tutorial, one which is easi…
... l
dontmove
'jr nz' stands for jump relative if ... score'
To cycle round the game before ... br /> cp 255
jr nz, checkright
inc hl ... br /> or c
jr nz, wait
Save, assemble, ... br /> cp 255
jr nz, checkright
inc hl ... -
Kiwi OS for z80 computerHi everyone, Nearly made my z80 computer with 2K ROM 32K RAM. It has an OS im still writing called Kiwi (apple, blackberry, you get the idea ;D) he…
... THE OPTION RUN
JR NZ, GOTO_COMPARE ;IF NOT RUN, ... THE OPTION GOTO
JR NZ, SAVE_COMPARE ;IF NOT RUN, ... THE OPTION GOTO
JR NZ, LOAD_COMPARE ;IF NOT SAVE, ... LOAD B WITH 8 (8 CLOCK CYCLES)
... LOAD B WITH 8 (8 CLOCK CYCLES)
LD A, ... -
Amazonia (BUGFIX)This is a bugfix for game [URL="http://www.worldofspectrum.org/infoseekid.cgi?id=0027280"]Amazonia[/URL], please add the following "known errors" des…
... /> 9ec7 21e99b ld hl,9be9h ; clock address
9eca 3e3c ld ... /> 9ec5 21e99b ld hl,9be9h ; clock address
9ec8 3e3b ld ... uppercase 'N'?
a4b6 20e7 jr nz,0a49fh ; otherwise wait for another ... -
Revisiting Spectrum CPU clock regenerationWarning: This post will be a bit nerdy :-) Some time ago, I experimented with phase locked loop circuits as a possible way to regenerate the Spectru…
... the Spectrum's clock and our regenerated clock each cycle of the ... 112MHz clock, and if the ... edge of the next Spectrum clock cycle, the regenerated signal is ... tick of the 112MHz clock per cycle. And by the beginning ... -
Double-Buffer ScreenFor my Alien Breed Speccy re-write I decided to use a Double Buffer (DB) or 'Back Screen' to draw all the game action onto, before shuffling the whol…
... reckon
dec a
jr nz,aloop
inc d ;Inc ... store it back again
jr nz,loop1 ;Back to Loop1 if ...
ld (cline), a
jr nz,loop1 ;Back to Loop1 for ... />
If anyone wants to clock how many FPS this can ... -
Hooky - hook ZX ROM and rewire RST and NMI to RAM - rantThis is a rather long rant. Not for short tempered. :) The objective is to hook into RST "vectors" and NMI on a Spectrum without affecting the normal…
... not part of a grand cycle timing scheme (and it ... (ROM TOP)?
0x11E0 JR NZ,downloop ; if not repeat
0x11E7 JR NC,test_2 ; if HL& ... 2-1=1
0x11EA JR Z,test)_2 ; bad value ... ; 1-1=0
0x11ED JR Z,uploop ; correct value!
type in to learn about IM2I'm trying to mess around with learning about IM2 and I found a nice little article in Sinclair User September 1988, issue 78, Page 70-71 [url="https…
... /> push HL
call CLOCK
pop HL
... ei
ret
CLOCK:
ld HL, $5818
dec (HL)
jr nz, PRINT_TIME
ld (HL), 50 ... /> [code]pasmo -v --tapbas clock.asm clock.tap[/code]
...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…
... not good at beer o'clock.
In the ... 8
dec c
jr nz, .nextbyte
ENDIF
call ... , e
or a
jr nz, .somethingpressed
inc a ; clear ... =0)
or a
jr nz, .nothalfline0
ld a, ( ...the happiest days of your life-pt2hello,again i have come up with 2 solutions to the problem of solving this game:- 1.the more people that try to solve this game (by combining diffe…
... #60
#DB92 JR C, #DB82
#DB94 JR NZ, #DBA8 ; Will jump ... the 100 Lines
#DBC5 JR NZ, #DC18 ; Exit routine if first ... Chapel) to get 17p Stamp (Cycle Sheds)
G.H. Annual ... ) = Typed Paper
17p Stamp (Cycle Sheds) + Sealed Envelope (Study 2 ...In Machine Code, what is the quickest way to sort bytes?I am playing around with some ordering of sprites, where I want to order them by vertical position. I used some Rodnay Zaks code to order some bytes…
... added complexity may waste more clock cycles than it saves on ...The Only Reason Sinclair Succeeded (Provoking Controversy)Although I love my Sinclairs dearly, I think that the only reason they succeeded was because at the time most people did not know any better (factori…
... carry will be set
jr c,Continue
ld (ix ... Loop
dec e
jr nz,Finish ; If E became zero ... continue
dec c
jr nz,Step
Finish:
ret ... if you look up the clock cycles by using page zero ...Fixing Attribute Clash via emulationI'm sorry if this has been posted already, but is there a possibility to fix attribute clash via emulation? I'm not talking about RealSpec or any of …
... next colour.
and 7 ; Cycle back to black when we ... time through the loop.
jr nz, again
halt ; Synchronize with ...48K sound effectsAnybody knows where could I find some small M/C routines to play tiny beeper sounds I could use in the 48K version of a game? I don't want the 48K pl…
... the length of each cycle
;bc holds ... /> or l
jr nz,PlaySFXLoop2
pop hl< ... /> or l
jr nz,PlaySFXLoop3
pop hl ... hl,bc ;vary the cycle length if bc is ... br /> or e
jr nz,PlaySFXLoop1 ; do it 'de ...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…
... 01
jr z, moveleft
jr moveright[/CODE]to ... and 1
jr nz,moveright
jr moveleft
[/code ... jr nz instead of jr z - my book says jr z takes only 7 clock ... pulses whereas jr nz ...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…
... 01
jr z, moveleft
jr moveright[/code]to ... jr nz instead of jr z - my book says jr z takes only 7 clock ... pulses whereas jr nz ... better to use jr (condition met) ... condition so I used NZ and MOVERIGHT.
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…
... jr nz instead of jr z - my book says jr z takes only 7 clock ... pulses whereas jr nz ... not always better to use jr (condition met) if one ... ]
All relative Jumps - JR xx - are slightly more expensive ...myspeccy.org - online gaming which auto-saves scoresIt's a blimmin' miracle - I'm most impressed.
... fix
CP $00
JR NZ, L_5CB0
INC A
L_5CB6: XOR A ; clock start fix
LD ($AB57 ... /> JP L_5CB6 ; DAY 1+2 clock start fix
ORG ... Jump bar, allowing the track clock to reset to 000.00 ...ZX Spectrum (16K) sound/beepHi all, I think I'm in right place now, I've tried to find an answer how to generate two channel sound using ZX Spectrum 16K. Only think I've found …
... counter for first channel.
JR NZ,labl1 ; Do we play the ... first half of the duty cycle.
LD A,16 ; Set ... first half of the duty cycle.
LD A,16 ; Set ... first half of the duty cycle.
LD A,16 ; Set ...What Z80 development tools do you use? What books?Hi. I've been meaning to do it for over 25 years, but.. better late than never :) I'm starting to learn machine code and am trying to get a developme…
... faster than 3.5mhz! Shaving clock cycles (the time the Z80 ... flag[/COLOR][/B]
jr nz,loop
;
[ ... l
; and a
; jr nz,loop2[/COLOR]
[B ... h
or l
jr nz,loop2[/B]
ret ...Games in machine codeHi everyone, How do go about doing multiple shots like a machine gun, do you have to store every x and y position of each bullet? When you kill som…
... /> fld qword [ebp+hermite_y1] ; Cycle buffer
fstp qword [ebp ... whole video frame/game cycle. Each task has ... c
jr nz,.c
dec b
jr nz,.b
and a,a
jr nz,.lz3
... ldh [cl],a
jr nz,.lz5
ldh ...Machine Code Routine of the weekHow about a thread that has a routine each week that is in [B]assembly language[/B] and is also described in great detail what the hell is going on …
... hl) ;compare priority
jr nc, add_beep1
ldi ; ... a
ret z
jr silent0
cycle
;E..duty ... br /> dec l
jr nz, peeb1
ld a, ...
dec h
jr nz, peeb0
ld a, ...New tool: ZXBOOT.EXE[B]ASM[/B] is proud to present the first release of ZXBOOT.EXE: [url]http://www.4shared.com/file/NP-FVOSf/zxboot__beta_.html[/url] ZXBOOT is a comma…
... same value! The previous depack cycle would have been a repeated ... b
db 32,0F9h ; jr nz,.fill
db 35 ... l
db 32,0E6h ; jr nz,.region
db 122 ... ,h
db 32,0E2h ; jr nz,.region
; ------------
< ...Requesting a little help to identify the purpose of this 'add-on' to my Issue 2Hi everyone First of all it's my first post here so please go easy on me! I'm grateful to be accepted into your fine little club :smile: I probabl…
... buc2 ld b,0 ;Cycle each address to hold valeus ... /> cp b ;equal?
jr nz,fallo ;if different, goto "fallo ... /> cp 0
jr nz,buc2 ;until we reach address ...
