-
Bit functions speedI just stared nonplussed at the documentation for the bit functions. Apparently, if you're using the accumulator, using AND and OR is faster than se…
... the use of CPI to test if BC is zero at the ... ]
inc hl
dec bc
ld a,b
[code]
cpi
jp pe, loop ; or ... -
Feelin' kinda proud of myselfOkay, it has bugs. But I kludged it together about 10 mins after getting the sprite thing to actually work. [url]http://britlion.googlepages.com/Spr…
... )
Increment and decrement directly, so
ld ... is that LDI does dec BC as well. Fortunately, we rarely ... cared about BC in these routines)
BC instead of in memory, which ... -
Feelin' kinda proud of myselfOkay, it has bugs. But I kludged it together about 10 mins after getting the sprite thing to actually work. [url]http://britlion.googlepages.com/Spr…
... )
Increment and decrement directly, so
ld ... is that LDI does dec BC as well. Fortunately, we rarely ... cared about BC in these routines)
BC instead of in memory, which ... -
FMV on +3eOK, so about 6 months ago i posted here that i got full motion video on +3e, with a bunch of scr files called passion. I added the glider rider music…
... ,table
exx
ld bc,49149
exx
ld ... bc,len
loop:
< ...
jr nz,deloop
cpi
jp pe,loop
Hi Res Print Routine neededHas anyone seen code for a print routine with pixel accuracy? That is print(y,x,CHAR) that allows 0 < y < 192 and 0 < x < 255 - that takes a charact…
... br /> ; Registers Used - AF,BC,DE,HL
; On ... Character Data
; BC Contains Y and X Position ... ld a,"X"
; ld bc,99*256+10 [Y Value ... :
;
; ld bc,99*256+10
; ld ... get the Counter value back, decrement it and go back for ...'Hello World' in ASM ?Can someone show how to make the classic 'Hello World' print with ASM code ? I cant figure at this moment how to insert and handle strings with the s…
... length of the block in BC. Internally it transfers data from ... HL and DE, decrements BC, and continue while BC!=0. It is ... ;increment destination address
dec bc ;decrement length
ld a,b ... /> jp nz,loop ;continue if BC!=0[/code]
...Hi Res Print Routine neededHas anyone seen code for a print routine with pixel accuracy? That is print(y,x,CHAR) that allows 0 < y < 192 and 0 < x < 255 - that takes a charact…
... : ld c,b
push bc
ld a,"A"
call print_char
pop bc
inc b
inc ... /> ;get the Counter value back, decrement it and go back for ...Z80 Machine Code Question...Hi Folks, I know not strictly a BASIC question but I have started to learn Z80 machine code - 25 years too late! :smile: I have been reading a book…
... inner loop and DJNZ to decrement B and jump if not ... .
[code]
LD BC, 14h ' Sets outer loop C ...Gigascreen - programming guideDoes anyone know of a programming guide for the 128K gigascreen screen mode, specifically a persistence colours table, some code (pref. C level or BA…
... ;A = 0
LD BC,254 ;BC = 254. I know OUT only ... = line below
LD BC,15*32 ;BC = 15 lines to do ... HL,BC ;Next screen row (+32 bytes)
DEC A ;Decrement counter ... :
flicker_loop
LD BC,32765 ;Output port for memory ...Move objectHi again, I am using paper colors to represent game objects. I have a "paddle" that is 4 pixels wide. I save its position as a 2 byte word in memory…
... />
dec hl ; decrement hl
djnz ... ; (DE) = (HL), DE ++, HL ++, BC--
ldi ; (DE) = ... (HL), DE ++, HL ++, BC--
ldi ; (DE) = ...Move objectHi again, I am using paper colors to represent game objects. I have a "paddle" that is 4 pixels wide. I save its position as a 2 byte word in memory…
... />
dec hl ; decrement hl
djnz ... ; (DE) = (HL), DE ++, HL ++, BC--
ldi ; (DE) = ... (HL), DE ++, HL ++, BC--
ldi ; (DE) = ...Thinking in Assembly (first efforts)The following is one small routine to educate myself on a few concepts (jumps, flow control, routines, CPI): [code]searchmem xor a …
... ret po
jr .search ; BC!=0
ret ; not found ... /> push hl
pop bc ; retrieve address
ret< ... the entire memory
.search cpi ; a-(HL)
ret ...Kobrahsoft DB1 - doesn't work?Hi, I've tried loading [URL="http://www.worldofspectrum.org/infoseek.cgi?regexp=^DB1$&pub=^Kobrahsoft$&loadpics=3"]DB1 by Kobrahsoft[/URL] into two …
... BC_SPACES with zero in BC, attempting to make " ... 00 10
LD BC, $0020 ; 8021 01 ... 00 C0
LD BC, $1E3C ; 802B 01 ... HL ; 803E EB
CPI ; 803F ED A1
...Up/Down Left/Right scrollCan anybody give a newbie some pointer to simple one char scrolling by pixel? I've looked at a lot of resources, but as you can imagine, it's all a …
... ,a
ld bc,face_sprites
add hl,bc
face_loop1 call ... now.
ld bc,face_sprites
add hl,bc
;if I ... use the DJNZ instruction to decrement B and loop back to ...Abbaye des morts[url]http://www.locomalito.com/juegos_abbaye_des_morts.php[/url] Looks like Spectrum, sounds like Spectrum, but it's not a Spectrum ('cause no colou…
... /> ld ixl,c ;Temporary transfer BC to IX
ld b ... IX (that is, decrement our copy of BC)
djnz RLEPut1byte
ld c,ixl ;Update BC counter after decoding a repetition ...Abbaye des morts[url]http://www.locomalito.com/juegos_abbaye_des_morts.php[/url] Looks like Spectrum, sounds like Spectrum, but it's not a Spectrum ('cause no colou…
... /> ld ixl,c ;Temporary transfer BC to IX
ld b ... IX (that is, decrement our copy of BC)
djnz RLEPut1byte
ld c,ixl ;Update BC counter after decoding a repetition ...Is there a ROM modification (48K) for load without typing LOAD""?The target is to play with 48K machines with keyboard broken, or an alternative solution for new clones like Superfo instead of making a new keyboard…
... .
; length of string in BC.
; start of string in ... value minus ten.
DEC BC ; decrement length.
; ten becomes nine ...IND/INDR/INI/INIR/OUTD/OTDR/OUTI/OTIRI'm looking for confirmation that the official Z80 User Guide from Zilog is wrong and that these composite instructions actually change the value of …
... hl,palette+15
ld bc,&10f8
otdr[/code ... from xz80), the OUT instructions decrement B before use, the IN ... instructions decrement after use. What do the ...IND/INDR/INI/INIR/OUTD/OTDR/OUTI/OTIRI'm looking for confirmation that the official Z80 User Guide from Zilog is wrong and that these composite instructions actually change the value of …
... hl,palette+15
ld bc,&10f8
otdr[/code ... from xz80), the OUT instructions decrement B before use, the IN ... instructions decrement after use. What do the ... Guide from Zilog says the BCHow to stop the +3 disk motorHi Folks. I was reading this thread [url]http://www.worldofspectrum.org/forums/showthread.php?t=32069[/url] and in post #17, Macc mentioned that the…
... />
[CODE]
.l387f ld bc,$7ffd
ld a,(BANKM ... a,($e600)
dec a ; decrement timeout
ld ($e600),a ... yet zero
.l389f ld bc,$1ffd ; address 14495 decimal
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…
... djnz.
djnz stands for Decrement then Jump if Not Zero ... over the instruction to increment / decrement the car position.
Replace ... to (de)),Decrement (hl and de) and Repeat (until bc is zero ...
gameover
pop bc ;retrieve score
pop hl ...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…
... hl,hl
add hl,bc
end asm
light1 ... ;'Counter for candles
ld bc,418 ;'Counter for bytes to ... in level
candles2:
cpi
jp po,candlesend
pop bc ; B=y
ex (sp ...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…
... ;'Counter for candles
ld bc,418 ;'Counter for bytes to ... in level
candles2:
cpi
jp po,candlesend
ld bc,417 ;'Counter for bytes to ... in level
candles2:
cpi
jr nz,candles3
Buzzer sounds tips'n'tricksSo I have an ARM Cortex M3 with a buzzer connected to its GPIO pin. And because I read this forum I know that there is no need to add a separate buzz…
... called the drum, remember to decrement your speed counter accordingly, to ...
snare: ld bc,$03fd ;if timing is off ...
inc hl
dec bc
ret
[/CODE]Machine code loopsDear all, 30 years too late I know, but I'm finally starting to get to grips with Machine Code - something I could never manage back in my early tee…
... you have,
[code] ld bc,n_iterations
.loop
;(some ... ;or dec hl
dec bc
ld a,b
bc,n_iterations
.loop
;(some kinda code)
cpi ;or ...Machine code loopsDear all, 30 years too late I know, but I'm finally starting to get to grips with Machine Code - something I could never manage back in my early tee…
... ] ld bc,n_iterations
.loop
;(some kinda code)
cpi ;or ... such an ingenious use of CPI/CPD before. This is one ...
