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Screen routinesHello. For my games I?m using the sprites routine method of a screen buffer and when I finish to print all the sprites I dump all the buffer in the …
... sprites
jr main
delay in a,(255)
cp ... +1),sp
ld hl,0 ;graphics
ld sp,scrntab ... loop
stk ld sp,0
ei
ret
ld e,(ix+0)
ld b,16
row11 defw 18528 ;row 11
defw 18784
defw ... -
64x48 full colour graphicsHow feasible is this? Could an interrupt-driven routine be used to, for example, fill the top two thirds with a 64x32 blocky picture and leave the bo…
... /> JP NZ,M3
;delay to reach the 1st line ... /> MV11 LD IY,10*256+11 ;IY
MV10 LD IX ... br />
LD A,36 ;delay
M6
DEC A ... />
StoreSP .WORD 0
.WORD 0
.WORD 0
StoreSP2 .WORD ... -
Some thoughs about fast scrolling on 128 modelPlease, consider this article as technically interesting concept not a proven algorithm. ONE The fastest scrollers use long sequence of PUSH inst…
... ;707054]Also a PUSH takes 11 cycles, or 16 when contended ... 8 possible values of contention delay: 6 or 5 or 4 ... or 2 or 1 or 0 or 0. Hence, on average you ... +2+1+0+0)/8=2.625
tacts of delay per screen ... -
Some thoughs about fast scrolling on 128 modelPlease, consider this article as technically interesting concept not a proven algorithm. ONE The fastest scrollers use long sequence of PUSH inst…
... /> +6 -> +5 -> +11
+5 -> +5 -> ... ; +5 -> +6
+0 -> +5 -> +5
+0 -> +4 -> +4[/ ... After this, the exact delay for the next instruction(s ... because the actual contention delay is deterministic and it depends ... -
How much does Bifrost improve graphics (test 192x192 graphics)Inspired by the BIFROST library I made several experiments with 8x1 graphics at 192x192 resolution. The results are now overwhelming but under certai…
... /> ; 15984T
PUSH DE ; columns 0 and 1
; 16000T
; 16123T
NOP ; extra delay to help sync on all ... /> PUSH DE ; columns 10 and 11
; 16144T
PUSH DE ... -
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…
... get remainder
ld b, 0 ; offset
ld c, a ... br /> nop ; 12 t-state delay
nop ; 8 t-state ... INT p)
fst 0 ; i to mem-0
fsub ; d ... , 0x98, 0x1f, 0xf5 ; mantissa (0.0577622606)
fmul ; d, pk ... -
Writing faster BASICIn terms of structuring BASIC programs, what are the best ways allocate variables, functions, arrays? Any tips. I remember INPUT mag had some suggest…
... 't actually doing a PAUSE 0 but a PAUSE 7997 as ... to PAUSE_1 which takes the delay from the BC register which ... 25 bytes whereas "PAUSE 0: CLS:" takes 11 bytes, plus as well ... -
A new full-screen bicolor engine called NIRVANA[I]OK, there's something I need to clarify first: Nowadays if you write [B]"multicolor"[/B] everyone assumes it refers to "multicolor 8x1" (an attri…
... />
ROWREPT = 0
N=0
dup TOTAL_ROWS
push hl ; columns 11 and 12
exx ... br /> sbc hl, hl ; extra delay
... -
Exploding routineI've been mucking about with 'Explode' from YS Program Pitstop, but I can not get it to work independently of the basic program. LET L=USR 61456 doe…
... to this area
k: delay factor. Greater values produces slower ... left corner, which is position (0,0). Range is to 255 and ... -
30-column 8x2 multicolor (even in 48K)I don't recall any 8x2 multicolor routine for 30 columns that would work on all Spectrum models (including the Spectrum 48K), so I decided to write i…
...
LD (nn),HL ; columns 0 and 1
LD HL ... /> PUSH DE ; columns 10 and 11
PUSH BC ; columns 8 ... 31
INC HL ; extra delay[/CODE] -
30-column 8x2 multicolor (even in 48K)I don't recall any 8x2 multicolor routine for 30 columns that would work on all Spectrum models (including the Spectrum 48K), so I decided to write i…
... LD (nn),HL ; columns 0 and 1
; ... PUSH DE ; columns 10 and 11
; 16095T
... 16248T
INC HL ; extra delay
; 16254T[/CODE]
... LD (nn),HL ; columns 0 and 1
; ... -
30-column 8x2 multicolor (even in 48K)I don't recall any 8x2 multicolor routine for 30 columns that would work on all Spectrum models (including the Spectrum 48K), so I decided to write i…
... loop starts) attributes for columns 0 and 1, in the first ... ; attributes for columns 10 and 11
LD HL,nn ; attributes ...
LD A,(HL) ; extra delay
LD (nn),HL ; update ... ,(nn) ; read attributes for columns 0 and 1
LD (nn ... -
30-column 8x2 multicolor (even in 48K)I don't recall any 8x2 multicolor routine for 30 columns that would work on all Spectrum models (including the Spectrum 48K), so I decided to write i…
... attributes for columns 10 and 11
; 15848T
0 and 1
; ... /> LD A,(HL) ; extra delay
; 15899T
... nn ; attributes for columns 0 and 1
... -
Detecting flash mode inversionsIs is possible to detect with certainty when flashing characters change from normal to inverted and vice-versa?
... br /> [code]
5 FLASH 0: CLS : FLASH 1
7 ... LET z =0
10 LET p= ... PEEK 23673*256)
11 IF INKEY$="q" THEN ... AT 0,0;" ": GO TO 10
40 PRINT AT 0,0; FLASH 0;" ... ";z;" ": GO TO 10
[/code]
just change delay ... -
Small Machine Code Routines Which Maybe UsefulAs part of creating Flynn's Adventure in Bombland I created a lot of little routines to do all sorts of things. A lot of these I created based on inp…
... />
[code]; Z80 variable delay routine
; by Hikaru in ...
; Usage: HL=delay, T states; HL > 123 ...
DELAY
ld bc,-124 ;10 ... 0 set means 1T delay
jr c,.d1 ;11/ ... set means 16T delay
ret nc ;11/27
