-
tiny routine to shift RAMTOP & stackCompressing some data areas above RAMTOP and wanting to make the released space available for BASIC arrays, I needed to move RAMTOP without using CLE…
... /> LD HL, 18 ; 33 18 0
ADD HL, SP ; 57
LD SP, HL ... -
BREAK from GOSUBHere's another one. Just in case you wanted to break out of multiple GOSUB levels with a single command, here's a routine to do it, tested on all mod…
... br /> [code]
RETSUB: LD HL, 20 ; 33 20 0 ;Discard ... & (ERR_SP)
LD SP, HL ; 249 ;from m/c ... )
EX DE, HL ; 235
LD (23613), SP ; 237 ... -
Procrustean PrintingHere's a short routine to manage printing of text with command tokens, to avoid messing up the screen when they are expanded. It just prints as many …
... ;
STACK: ld hl,14
add hl,sp
ld sp,hl ;undo USR ... ,hl ;HL=string pointer
ld b,a ;B =max_length
SSNEXT1:ld a,(hl ... -
Invalid combination of operands and opcodesIt says the error in the title, why is this?? [CODE] ORG 0000 LD HL, 63000 ;LOAD HL WITH STACK LOCATION LD SP, HL ;SET STACK POINTER TO HL LD A, …
...
LD HL, 63000 ;LOAD HL WITH STACK LOCATION
LD SP, HL ;SET STACK ... TO DISPLAY
LD HL, 0000 ;LOAD HL WITH THE STARTING ... TO DISPLAY
LD HL, 0000 ;LOAD HL WITH Z80 POWERED ... THE COMMAND
LD HL, 0000 ;LOAD HL WITH CLEAR LINE TEXT ... -
Indirect Variable AssignmentHere's another wacky routine. This allows assignment of values to variables where the source & destination variables can themselves be defined in var…
Here's another wacky routine. This allows assignment of values to variables where the source & destination variables can themselves be defined in variables (or expressions which evaluate to variables). Some of this can already be done with VAL or VAL$, ... -
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…
... /> 9ec1 210000 ld hl,0000h
9ec4 22c89b ld (9bc8h),hl ; reset time ... ret
9ee0 3600 ld (hl),00h ; reset minutes/hours/ ... already zero)
9ec5 21e99b ld hl,9be9h ; clock address
... -
Undefine functionHere's a routine to selectively remove variables from the VARS area and reclaim the space. This can be done partially from BASIC already by assigning…
... "];
UNDEF: ld hl,14
add hl,sp
ld sp,hl ;undo USR ... /> STRARR: inc hl
ld c,(hl)
inc hl
ld b,(hl) ;BC=length ... -
A z88dk + sp1 demo (with source)Since nowadays people are still wondering about how difficult it is to make something in z88dk, I thought I just put a very simple demo to show how e…
Since nowadays people are still wondering about how difficult it is to make something in z88dk, I thought I just put a very simple demo to show how easy it actually is. (Actually I've already published this one some time ago, but this time the source is ... -
Loading the display with data from memoryTrying to load part of the screen(4k's worth) with data from memory location 53000, I've written this routine, but it doesnt work... [I]ld b,4000 ld…
... ]ld b,4000
ld de, 16384
ld hl, 55000
loop ld a,(hl ... )
ld (de ... ),a
inc de
inc hl
S-S-Sample black borderI'm wanting the 'S-S-Sample' routine from YS to play the sounds without the flashing border effects. A plain black border is required. Heres the rou…
... /> ld hl, (32768 )
ld de, (32770)
ld bc, 2048
ld c, (hl)
ld ... a, c
rlca
ld ...joining lines of BASICDue to overwhelming demand - well, one demand - well, more of a suggestion, really - here's a routine to join together lines of BASIC. The vertical c…
... ld (hl),a
inc hl
ld c,(hl)
ld (hl),a
inc hl
ld ... b,(hl)
ld (hl ...The INPUT command routine ($2089)I was looking at the INPUT routine with a view to modifying the intro so that I could pre-load the workspace and edit an existing value, rather than …
... .
2161 IN-VAR-4 LD (K-CUR-hi),+00 The ... is copied to[/color]
LD BC,(ECHO-E) [color=red ... .
2174 IN-VAR-5 LD HL,+5C71 This is FLAGX.
editing strings with INPUT LINEHere's the latest in my unpredictable series of utility routines. This one I needed for the SAGE game editor; it emulates INPUT LINE l$ but with the …
... de,hl
ld (hl),$0d ;followed by ENTER
ld (K_CUR),hl
ld de ... ,LNAME
ld ...AZIMUT / Frecuency spectrum[code]start DI LD HL,#7F40 LD D,#58 loop LD B,#00 bucle1 LD A,H IN A,[#FE] XOR A,C AND A,L J…
... DI
LD HL,#7F40
LD D,#58
loop LD B,#00 ... bucle1
findA LD E,B
LD A,[DE]
INC ... ,H
LD [DE],A
LD C,#00
LD A,H ...Routine for clearing screenI was looking for a 'nice' way of clearing a screen of graphics in Z80. After a ridiculous amount of time mucking around, this is the best and most …
...
ld hl,16384
ld bc,6144
ld de,(PRT_CHR ... ld a,(hl)
and e
ld (hl),a
inc hl ...
dec bc
ld a ... ,SCREEN_CLEAR_LOOP
ld a,(PRT_CHR)
sla a ... ret nc
ld (PRT_CHR),a
jr ...28-character wide multicolour(ish) on 48k SpectrumLong-time lurker here... I've always been interested in rainbow effects on the 48k Spectrum, mainly from a perspective of "Just what [I]would [/I]ha…
... /> LD H,A
LD A,24
LD (DEPTH),A
LD (HIATT),HL ... ; Some more attribute data
ld hl,5566H ; Some more attribute data ... /> LD L,C
LD D,A
LD E,B
LD (HL),0FDH ...Inefficient code in ROM, from ram-check to RAM-DONEHere is the inefficient code: [CODE] ;; ram-check L11DA: LD H,D ; Transfer the top value to the HL register LD L,E …
... to the HL register
LD L,E ... RAM-FILL
L11DC: LD (HL),$02 ; Load memory with $02 ... paper.
DEC HL ; Decrement memory address ... RAM-FILL
L11DA: LD (HL),$01 ; Load memory with $ ...Help pleeease "Proving Emulator OpCode flags are correct"So I had a cunning plan... I wanted to write a test harness for Emulators that could "prove" that all opcode flags were correct. I wanted something m…
... :
LD HL,0x7000 //mcAddr, lAddr
LD IX,0x8000 //xAddr ...
LD B,0 //aAddr
LD C,0 //fAddr ...
LD D,0 //dAddr ... br /> POP DE
LD (HL),D
LD (IX+0),E
Byte-order backbufferThis is a tool for Z80 coders who wish the Spectrum screen had a serial layout. It runs as an interrupt mode 2 service routine and uses POP and PUSH …
... byte of the screen
ld hl, $ + 9 ; set return location (no ... stack available)
ld (endcall), hl
jp blit ; call ... ) - (chunk * 2048)
ld hl, $ + 9
ld (endcall), hl
jp blit
Screen2StringFurther to writing that BASIC one-liner to redirect CAT to a string I thought that I'd do a general redirection routine for anything which normally p…
... code
REM ld hl,(ptr) : ld (hl),a : inc hl : ld (ptr),hl : ret
DATA ...What's wrong with this code ?OK, working my way through Jonathan Cauldwells 'How To' tome and I can't get the following to run in either spin or basin. ( iused the assembler in b…
... graphics.
ld hl,blocks ; address of user ... ld hl,21+15*256 ; load hl pair with starting coords.
ld (plx),hl ... br />
mpl ld hl,ply ; remember, y ... br />
mpr ld hl,ply ; remember, y ...Moving a line down the display in assembler?...It's not a "[I]how can I do it[/I]" question, it's more a "am I missing something in trying to do it a new way" kinda question. What I've been doing…
... /> [CODE]
ld hl,16384
ld b,8
loop1: ld (hl),255
hl)
inc h
ld h,(hl)
ld l,a
ld (hl ...CMWC random number generator for Z80Seeing the interest regarding the [URL="http://www.worldofspectrum.org/forums/showthread.php?t=23070"]Xor-Shift random number generator for Z80[/URL]…
... /> ld b,0
ld c,e
ld hl,table
add hl,bc ...
ld c,(hl ... = ~x
pop hl
ld (hl),a ; q[i] = x ...Jelly-Vision!As threatened in the "'Spectrum Play' Error" thread, here's a ruff'n'reddy interrupt driven full screen wobbling routine which has no practical use w…
... : push hl
ld hl,0005
add hl,sp
ld a,(hl)
cp ... ,MOVEUP
MOVEDOWN: ld hl,16384+256
ld de,16384
ldir ...Developing apps for ZX Spectrum with SDCCDue to troubles with makebin utility which always starts coversion at memory address 0x0000 and can only produce binaries < 32KB, it can't be used to…
... /> AS = as-z80
LD = sdcc
LIB = ar ... br /> app.bin: $(OBJS)
$(LD) $(LDFLAGS) $^
./makezxbin app.bin ... _HEADER(ABS)
ld (#store_sp),sp ; store SP
_get_heap:: ld hl,#heap
ret
Hep needed with a bit of code...I've written a bit of code to make a character move across the screen, but the counter stops at 29 when the 3 lines to delete the characters trail ar…
... ; ????
ld hl, 63289
dec (hl)
dec (hl)
ld a,(63289 ... /> call 5633
ld bc, 10
ld de, 63290
call ... /> ret
prb: ld a,(63289)
ld (63298 ),a
call ...40 Column Printing RoutineI've written a 40 column printing routine, which I'd like to share... It's my first piece of 'public' code so go easy on me! I don't think it is a…
... /> ld hl,overscratch
overpopulate ld (hl),%00000011
inc hl
ld (hl),255
inc hl ...merging bytesPicturing three bytes with their bits identified by letters to make the visualisation easier, what's the best way to perform this transformation? [co…
...
ld (hl),a
inc hl
[color=red] ld a,(hl) ;ld a,b ... /> or d ;A=FGHlmnop
ld (hl),a
ret
[/code ...next pixelI searched the "Discussions" groups for the phrase "next pixel" and got no matches - and removing the quotes it discards the "next" and just searches…
... ld hl,$4000
ld de,$4000
ld bc,0
pixrow: ld (hl ... /> jr z,set_hl
ld d,%01000000
inc c ... inc b ;B =segment
ld a,b
cp 3 ...
