-
Look whats possible in 924 bytesSo, finally after over a year of development and nearly 25 years since I first designed the graphics, I've actually made it to the point where this i…
... /> ld de,0fcc0h
ld bc,0009h
ldir
ld ... I can also use 1 register for the counter instead of ... -
c64 .sid player coming soon to specy 128!!!c64 .sid player coming soon to specy 128!!! the first old version uses only square waves, 4 years ago: https://www.youtube.com/watch?v=6CKt9noxA7s…
... to accessing a non-existent register:
[code]< ... bc,#FFFD
xor a
out (c),a ;select AY register ... (c),l ;select "AY register 16" (it does not ... return the contents of the register 0 (#40)
...
c64 .sid player coming soon to specy 128!!!c64 .sid player coming soon to specy 128!!! the first old version uses only square waves, 4 years ago: https://www.youtube.com/watch?v=6CKt9noxA7s…
... check block length in DE register before data loading.
40 RANDOMIZE USR codeAB
50 GOTO 30 ... set correct length in DE register before #556 call.
Look whats possible in 924 bytesSo, finally after over a year of development and nearly 25 years since I first designed the graphics, I've actually made it to the point where this i…
...
no_piece:
pop bc
inc c ... 7 of the data register lo-byte to determine ... inc a
ld (bc),a
ldi
...Look whats possible in 924 bytesSo, finally after over a year of development and nearly 25 years since I first designed the graphics, I've actually made it to the point where this i…
...
no_piece:
pop bc
inc c ... 7 of the data register lo-byte to determine ... inc a
ld (bc),a
ldi
...The HL Register Pair Naming. An Observation.This isn’t really a question or a tip. Just an observation about the naming convention of the registers in the Z80 CPU. It seems that every register …
... made more sense to choose BC for counter and DE for ... kinda forced them to use BC for the count.
register and INI and OUTI (and ... use the low byte of BC if a count is only ... forced their hand as sending BC to the address bus was ...New ZEsarUX beta - RC2Hi I have uploaded a new ZEsarUX beta version on the usual url https://sourceforge.net/projects/zesarux/files/Beta_and_Snapshot_versions/ This…
... equ $CF3B ; ZEsarUX ZXI Port register (53051)
ZXIPORTDAT equ $ ... /> TESTDBGPRTLP1 equ $
LD BC,ZXIPORTREG
LD A,ZXIPORTCHR ... OUT (C),A
LD BC,ZXIPORTDAT
LD A,' '
z80 Helper?When you are programming with z80 do you get 'lost' you are in the middle of making a routine and you can't remember which registers are holding val…
... there is some value in register, read it again if you ... can
[code]LD BC,31
IN A,(C ... /> LD DE,16385
LD BC,6911
LD (HL),0 ... /> LD DE,16385
LD BC,6911
LD (HL),L ... /> LD DE,30001
LD BC,9999
LD (HL),L ...z80 Helper?When you are programming with z80 do you get 'lost' you are in the middle of making a routine and you can't remember which registers are holding val…
... ,
you can use a register to keep track of the ... /> Instead of
LD BC,(34567)
why not ... :
ReadRam(34567,BC)
instead of:
z80 Helper?When you are programming with z80 do you get 'lost' you are in the middle of making a routine and you can't remember which registers are holding val…
... ,
you can use a register to keep track of the ... /> Instead of
LD BC,(34567)
why not ... :
ReadRam(34567,BC)
instead of:
z80 Helper?When you are programming with z80 do you get 'lost' you are in the middle of making a routine and you can't remember which registers are holding val…
... A load/store with other register pairs takes 40 cycles ... outward from there. Optimal register assignment and stack usage will ... move to an index register to index items randomly. ... like "pop af; pop bc; push bc; push af" to ... on the stack (now in BC) or "ld hl,n ...z80 Helper?When you are programming with z80 do you get 'lost' you are in the middle of making a routine and you can't remember which registers are holding val…
... br /> Loop3
ld a,(bc)
cp 0
... /> rst $10
inc bc
inc de
jr ... /> rst $10
inc bc
inc de
jr ... let the user say which register pair is used in the ...The trouble with good code isLots of times I've come here to ask for help and always got it pretty promptly. Which is wonderful and one of the reasons why I don't think there's a…
... single byte or 8 bit register :P
Or 65536 if ... you use two bytes / a register pair (BC, HL).
Machine ...Reading Disks via ASMI'm hoping to port my Amstrad game to the spectrum (See the link in my sig for info) I will be targeting the 128 and +3 - the game will not work on …
... u(a$,f$,B,D)=USR DOS", summarised thus:
USR DOS: B=bc=FN b(c,b ...The point of IX+1 IX+2 ?the numbers that you can add-on to IX and IY seem hardcoded, so I dont see the use of that feature? any examples of the use of IX and IY plus number…
... ld a,FCH_ADD_HP
ld bc,20
jp ... by name in the "A" register. In this case "FCH_ADD_HP" ... to a character
; bc = amount of health to add ... points
add hl,bc ; increase health
what is wrong with this loop?here is the loop: ld b,12 ld a,31 ld de,right_screen_array right_screen_array_label call charaddress ex de,hl ;de now contains screen address…
... "][code]push af
push bc
call charaddress
pop ... bc
pop af[/code]
< ... at least half of a register pair to pass back result ...what is wrong with this loop?here is the loop: ld b,12 ld a,31 ld de,right_screen_array right_screen_array_label call charaddress ex de,hl ;de now contains screen address…
... "][code]push af
push bc
call charaddress
pop ... bc
pop af[/code]
< ... at least half of a register pair to pass back result ...shadow regs musingIn the process of optimising some assembler, it occurred to me how great it would have been if the Z80's shadow reg opcodes had been a bit more fully…
... to complete two sets of register files including the program counter ... , the set of general purpose register, and exchanging the set of ... two separate exchange opcodes for "BC, DE, HL" and "AF ...ZX Spectrum Z80 Development Environment on WindowsHi Folks, Just wondering what the recommendation is for a ZX Spectrum Z80 Development environment on Windows? Getting fed up with hand coding Z80…
... bc, 49151
ret
[/code]
Assemble this, then "PRINT USR ...ZX Spectrum Z80 Development Environment on WindowsHi Folks, Just wondering what the recommendation is for a ZX Spectrum Z80 Development environment on Windows? Getting fed up with hand coding Z80…
... bc, 49151
ret
[/code]
Assemble this, then "PRINT USR ...ZX Spectrum Z80 Development Environment on WindowsHi Folks, Just wondering what the recommendation is for a ZX Spectrum Z80 Development environment on Windows? Getting fed up with hand coding Z80…
... you could somehow use another register in there anyway), or EXA ... ,E,F: PUSH AF,HL,BC: RET' and especially stuff like ...ZX Spectrum Z80 Development Environment on WindowsHi Folks, Just wondering what the recommendation is for a ZX Spectrum Z80 Development environment on Windows? Getting fed up with hand coding Z80…
... you could somehow use another register in there anyway), or ... E,F: PUSH AF,HL,BC: RET' and especially stuff ... [code]
ldi (iy+nn),bc
ldi l,(hl)
sub hl,bc
[/code]
BC,IX" I honestly have no ...Thought this would be simple... Z80Hi Folks, Started to read "Beyond simple BASIC, Delving Deeper into your ZX Spectrum" by Dilwyn Jones. This is a great book and I came across the…
... variable. You can also use register pairs directly to pass the ...
draw
ld bc,$18c ;1 into B, 200 ...Thought this would be simple... Z80Hi Folks, Started to read "Beyond simple BASIC, Delving Deeper into your ZX Spectrum" by Dilwyn Jones. This is a great book and I came across the…
... to normal registers
ld bc,$00FF ; B=Y, C=X ... CLS
110 LET I=USR 63000
120 STOP
Thought this would be simple... Z80Hi Folks, Started to read "Beyond simple BASIC, Delving Deeper into your ZX Spectrum" by Dilwyn Jones. This is a great book and I came across the…
... n=1 TO 100: RANDOMIZE USR address: NEXT N
3 ... of screen file
ld bc,$18 ;0 into B; 8 ...Thought this would be simple... Z80Hi Folks, Started to read "Beyond simple BASIC, Delving Deeper into your ZX Spectrum" by Dilwyn Jones. This is a great book and I came across the…
...
push bc ; Store BC registers
... ,ATTR_ROW_CHAR
pop bc ; Restore BC registers
pop ... /> 170 LET A=USR 63000
180 ...
