I have received a request to make a program version compatible with the TI-83/TI-82 STAT. I understand that I won't be working with flash or bcalls, but how do I make assembly programs for them? What do I have to do with the compiler to make it compile as a .83p? By the way, I am working with the DCS SDK.
Asm(EB0E45ED680CED60ED52 The way this will work is that you can run this once with a 0 on the previous line and store the result to a variable. This will be an offset that can be used later. When you run this again, later, make sure the variable with the offset is on the line before. This will then output the number of seconds that have passed since it was used the first time. Um, here is an example:
0 Asm(EB0E45ED680CED60ED52 ;Stores the current timer state to Ans →T <<code>> T ;T will be subtracted from the current timer state Asm(EB0E45ED680CED60ED52 ;Ans will be the number of seconds (up to 65535) since the timer was initially tested
Here are a few that I really, really like and are the first to come to mind (there are tons more): Ellen Hopkins -Glass -Crank -Impulse -Burned -Identical -Tricks Robert Jordan -The Wheel Of Time series J.K. Rowling -The Harry Potter series Eoin Colfer -Airman -The Artemis Fowl series -The Supernaturalist -The Wish List Nancy Farmer -The House of the Scorpion J.R.R. Tolkein -The Lord of the Rings series -The Hobbit Lewis Carroll -The Chronicles of Narnia Suzanne Collins -The Hunger Games books Terry Goodkind -The Sword of Truth series Tess Gerritsen -Bloodstream Christopher Paolini -The Inheritance series
My favorite activities follow this order: Exploring math Reading Programming Eating ice cream
Yeah, I know, but I just wanted to give an example. It is really only the last few bytes that are important, though, and I wanted to give a simple, easy to follow example. Also, great job with the optimisations I wish I could help more, but most of the codes are a bit beyond my optimisation abilities.
My computer is about to die and my charger is broken. Anyway, I am onto something that might let me give y'all an equation that produces all the primes in the form of 2n+1. Would that help in any way? Also, I cannot make any guarantees about this, it is just a hunch.
Spoiler For Spoiler:
If I am right, this is a prime number (assuming my calculations are correct): 20035299304068464649790723515602557504478254755697514192650169737108940595563114530895061308809333481010382343429072631818229493821188126688695063647615470291650418719163515879663472194429309279820843091048559905701593189596395248633723672030029169695921561087649488892540908059114570376752085002066715637023661263597471448071117748158809141357427209671901518362825606180914588526998261414250301233911082736038437678764490432059603791244909057075603140350761625624760318637931264847037437829549756137709816046144133086921181024859591523801953310302921628001605686701056516467505680387415294638422448452925373614425336143737290883037946012747249584148649159306472520151556939226281806916507963810641322753072671439981585088112926289011342377827055674210800700652839633221550778312142885516755540733451072131124273995629827197691500548839052238043570458481979563931578535100189920000241419637068135598404640394721940160695176901561197269823378900176415171900511334663068981402193834814354263873065395529696913880241581618595611006403621197961018595348027871672001226046424923851113934004643516238675670787452594646709038865477434832178970127644555294090920219595857516229733335761595523948852975799540284719435299135437637059869289137571537400019863943324648900525431066296691652434191746913896324765602894151997754777031380647813423095961909606545913008901888875880847336259560654448885014473357060588170901621084997145295683440619796905654698136311620535793697914032363284962330464210661362002201757878518574091620504897117818204001872829399434461862243280098373237649318147898481194527130074402207656809103762039992034920239066262644919091679854615157788390603977207592793788522412943010174580868622633692847258514030396155585643303854506886522131148136384083847782637904596071868767285097634712719888906804782432303947186505256609781507298611414303058169279249714091610594171853522758875044775922183011587807019755357222414000195481020056617735897814995323252085897534635470077866904064290167638081617405504051176700936732028045493390279924918673065399316407204922384748152806191669009338057321208163507076343516698696250209690231628593500718741905791612415368975148082619048479465717366010058924766554458408383347905441448176842553272073155863493476051374197795251903650321980201087647383686825310251833775339088614261848003740080822381040764688784716475529453269476617004244610633112380211345886945322001165640763270230742924260515828110703870183453245676356259514300320374327407808790562836634069650308442258559670392718694611585137933864756997485686700798239606043934788508616492603049450617434123658283521448067266768418070837548622114082365798029612000274413244384324023312574035450193524287764308802328508558860899627744581646808578751158070147437638679769550499916439982843572904153781434388473034842619033888414940313661398542576355771053355802066221855770600825512888933322264362819848386132395706761914096385338323743437588308592337222846442879962456054769324289984326526773783731732880632107532112386806046747084280511664887090847702912081611049125555983223662448685566514026846412096949825905655192161881043412268389962830716548685255369148502995396755039549383718534059000961874894739928804324963731657538036735867101757839948184717984982469480605320819960661834340124760966395197780214411997525467040806084993441782562850927265237098986515394621930046073645079262129759176982938923670151709920915315678144397912484757062378046000099182933213068805700465914583872080880168874458355579262584651247630871485663135289341661174906175266714926721761283308452739364692445828925713888778390563004824837998396920292222154861459023734782226825216399574408017271441461795592261750838890200741699262383002822862492841826712434057514241885699942723316069987129868827718206172144531425749440150661394631691976291815065797455262361912248480638900336690743659892263495641146655030629659601997206362026035219177767406687774635493753188995878662821254697971020657472327213729181446666594218720034745089428309115351892711142871083761592223802766053278233516615551493693757784666701457179719012271178127804502400263847587883393968179629506907988171216906869295382485298300234760684541141781391106485602365497542274972310076151318700240539105109138178437217914225285874320985249578780346837033378184214440171386881242499844186181292711985333153825673218704215306311977485352146709553346263366108646673322924098798492566911095161436186015489097402419135096230436121961281659505186660220307156136847323646608689050142639139065150639081993788523183650598972991254044794434251667742996598118492331515552728832740283526884424087528112832899806259126736995462473415433335001472314306127503903073971352520693381738433229507010490618675394331307847980156551303847581556852362180104196502555961819349863159132330360964619059902361126811960234418433633345949276319461017166529138237171823942992162725384617760656945422978770713831988170369645886898118632109769003557358846244648357062914530527571012788720279653644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ld a,c ld c,b ld hl,0 ld b,16 Mul_Loop_1: add hl,hl add a,a rl c jr nc,$+3 add hl,de djnz Mul_Loop_1 ret
I like this method for speeding things up! This is exactly the kind of thing I was hoping for. I want to understand how to program better, so the more ideas I can learn, the better off I should be on my quest
C_Div_D: ;Inputs: ; C is the numerator ; D is the denominator ;Outputs: ; A is the remainder ; B is 0 ; C is the result of C/D ; D,E,H,L are not changed ; ld b,8 xor a sla c rla cp d jr c,$+4 inc c sub d djnz $-8 ret
DE_Times_A: ;Inputs: ; DE and A are factors ;Outputs: ; A is not changed ; B is 0 ; C is not changed ; DE is not changed ; HL is the product ; ld b,8 ld hl,0 add hl,hl rlca jr nc,$+3 add hl,de djnz $-5 ret
DE_Times_BC: ;Inputs: ; DE and BC are factors ;Outputs: ; A is 0 ; BC is not changed ; DE is 0 ; HL is the product ; ld hl,0 ld a,16 Mul_Loop_1: add hl,hl ex de,hl add hl,hl ex de,hl jr nc,$+3 add hl,bc dec a jr nz,Mul_Loop_1 ret
DEHL_Div_C: ;Inputs: ; DEHL is a 32 bit value where DE is the upper 16 bits ; C is the value to divide DEHL by ;Outputs: ; A is the remainder ; B is 0 ; C is not changed ; DEHL is the result of the division ; ld b,32 xor a add hl,hl ex de,hl adc hl,hl ex de,hl rla cp c jr c,$+4 inc l sub c djnz $-10 ret
;=============================================================== DEHL_Times_A: ;=============================================================== ;Inputs: ; DEHL is a 32 bit factor ; A is an 8 bit factor ;Outputs: ; interrupts disabled ; BC is not changed ; AHLDE is the 40-bit result ; D'E' is the lower 16 bits of the input ; H'L' is the lower 16 bits of the output ; B' is 0 ; C' is not changed ; A' is not changed ;=============================================================== di push hl or a sbc hl,hl exx pop de sbc hl,hl ld b,8 mul32Loop: add hl,hl exx adc hl,hl exx add a,a jr nc,$+8 add hl,de exx adc hl,de inc a exx djnz mul32Loop push hl exx pop de ret
GCDHL_BC: ;Inputs: ; HL is a number ; BC is a number ;Outputs: ; A is 0 ; BC is the GCD ; DE is 0 ;Destroys: ; HL ;Size: 25 bytes ;Speed: 30 to 49708 cycles ; -As slow as about 126 times per second at 6MHz ; -As fast as about 209715 times per second at 6MHz ;Speed break down: ; If HL=BC, 30 cycles ; 24+1552x ; If BC>HL, add 20 cycles ; *x is from 1 to at most 32 (because we use 2 16-bit numbers) ; or a \ sbc hl,bc ;B7ED42 19 ret z ;C8 5|11 add hl,bc ;09 11 jr nc,$+8 ;3006 11|31 ld a,h ;7C -- ld h,b ;60 -- ld b,a ;47 -- ld a,l ;7D -- ld l,c ;69 -- ld c,a ;4F -- Loop: call HL_Div_BC ;CD**** 1511 ld a,d \ or e ;7AB2 8 ret z ;C8 5|11 ld h,b \ ld l,c ;6069 8 ld b,d \ ld c,e ;424B 8 jr $-10 ;18F8 12
EDIT: 25-March-2015 This has been really in need of updating and optimizing. This version is 226cc to 322cc faster than the original for 2 bytes more.
;=============================================================== DE_Div_BC_round: ;=============================================================== ;Performs DE/BC, rounded ;Speed: 1172+6b cycles, 1268cc worst case ;Size: 25 bytes ;Inputs: ; DE is the numerator ; BC is the denominator ;Outputs: ; DE is the quotient ; BC is divided by 2 (truncated) ; A reflects the low bits of the quotient ;Destroys: HL ;=============================================================== ld a,d ld hl,0 ld d,16
rl e rla adc hl,hl sbc hl,bc jr c,$+3 add hl,bc dec d jr nz,$-11 cpl ld d,a ld a,e cpl ld e,a ret
HL_Div_C: ;Inputs: ; HL is the numerator ; C is the denominator ;Outputs: ; A is the remainder ; B is 0 ; C is not changed ; DE is not changed ; HL is the quotient ; ld b,16 xor a add hl,hl rla cp c jr c,$+4 inc l sub c djnz $-7 ret
HLDE_Div_C: ;Inputs: ; HLDE is a 32 bit value where HL is the upper 16 bits ; C is the value to divide HLDE by ;Outputs: ; A is the remainder ; B is 0 ; C is not changed ; HLDE is the result of the division ; ld b,32 xor a ex de,hl add hl,hl ex de,hl adc hl,hl rla cp c jr c,$+4 inc e sub c djnz $-10 ret
EDIT 16 Aug 2019: A less destructive nCr routine that isn't prone to overflow in intermediate calculations can be found here.
;=============================================================== nCrHL_DE: ;=============================================================== ;Inputs: ; hl is "n" ; de is "r" ;Outputs: ; interrupts off ; a is 0 ; bc is an intermediate result ; de is "n" ; hl is the result ; a' is not changed ; bc' is "r"+1 ; de' is the same as bc ; hl' is "r" or the compliment, whichever is smaller ;=============================================================== or a ;reset carry flag sbc hl,de ret c ;r should not be bigger than n sbc hl,de \ add hl,de jr nc,$+3 ex de,hl ;hl is R push de ld bc,1 ;A exx pop de ;N ld bc,1 ;C ld h,b \ ld l,c ;D nCrLoop: push de push hl call DE_Times_BC push hl \ exx \ pop de push hl call DE_Div_BC pop de push hl \ ex de,hl \ exx \ pop hl ld b,h \ ld c,l pop de \ add hl,de pop de \ inc de exx inc bc or a \ sbc hl,bc \ add hl,bc exx jr nc,nCrLoop ret
RoundHL_Div_C: ;Inputs: ; HL is the numerator ; C is the denominator ;Outputs: ; A is twice the remainder of the unrounded value ; B is 0 ; C is not changed ; DE is not changed ; HL is the rounded quotient ; c flag set means no rounding was performed ; reset means the value was rounded ; ld b,16 xor a add hl,hl rla cp c jr c,$+4 inc l sub c djnz $-7 add a,a cp c jr c,$+3 inc hl ret
;=============================================================== sqrtE: ;=============================================================== ;Input: ; E is the value to find the square root of ;Outputs: ; A is E-D^2 ; B is 0 ; D is the rounded result ; E is not changed ; HL is not changed ;Destroys: ; C ; xor a ;1 4 4 ld d,a ;1 4 4 ld c,a ;1 4 4 ld b,4 ;2 7 7 sqrtELoop: rlc d ;2 8 32 ld c,d ;1 4 16 scf ;1 4 16 rl c ;2 8 32
rlc e ;2 8 32 rla ;1 4 16 rlc e ;2 8 32 rla ;1 4 16
cp c ;1 4 16 jr c,$+4 ;4 12|15 48+3x inc d ;-- -- -- sub c ;-- -- -- djnz sqrtELoop ;2 13|8 47 cp d ;1 4 4 jr c,$+3 ;3 12|11 12|11 inc d ;-- -- -- ret ;1 10 10 ;=============================================================== ;Size : 29 bytes ;Speed : 347+3x cycles plus 1 if rounded down ; x is the number of set bits in the result. ;===============================================================
;=============================================================== sqrtE: ;=============================================================== ;Input: ; E is the value to find the square root of ;Outputs: ; A is E-D^2 ; B is 0 ; D is the result ; E is not changed ; HL is not changed ;Destroys: ; C=2D+1 if D is even, 2D-1 if D is odd
rlc e ;2 8 32 rla ;1 4 16 rlc e ;2 8 32 rla ;1 4 16
cp c ;1 4 16 jr c,$+4 ;4 12|15 48+3x inc d ;-- -- -- sub c ;-- -- -- djnz sqrtELoop ;2 13|8 47 ret ;1 10 10 ;=============================================================== ;Size : 25 bytes ;Speed : 332+3x cycles ; x is the number of set bits in the result. This will not ; exceed 4, so the range for cycles is 332 to 344. To put this ; into perspective, under the slowest conditions (4 set bits ; in the result at 6MHz), this can execute over 18000 times ; in a second. ;===============================================================
It doesn't matter if they are optimised for speed or size, I just want to know what optimisation tricks I still need to establish. I just copied these out of my math routines folder, so some of them have random scratch work with them...
I was toying around with some math routines while I was away and I was curious about the square root algorithms. Are the designed to return the square root rounded down, up, or just rounded? If it is rounded down and you want to round it to the nearest integer answer, here is a code I made a while ago (it isn't even close to what Axe needs, but it should only be taken as an example):
;=============================================================== sqrtE: ;=============================================================== ;Input: ; E is the value to find the square root of ;Outputs: ; A is E-D^2 ; B is 0 ; D is the rounded result ; E is not changed ; HL is not changed ;Destroys: ; C ; xor a ;1 4 4 ld d,a ;1 4 4 ld c,a ;1 4 4 ld b,4 ;2 7 7 sqrtELoop: rlc d ;2 8 32 ld c,d ;1 4 16 scf ;1 4 16 rl c ;2 8 32
rlc e ;2 8 32 rla ;1 4 16 rlc e ;2 8 32 rla ;1 4 16
cp c ;1 4 16 jr c,$+4 ;4 12|15 48+3x inc d ;-- -- -- sub c ;-- -- -- djnz sqrtELoop ;2 13|8 47 cp d ;1 4 4 jr c,$+3 ;3 12|11 12|11 inc d ;-- -- -- ret ;1 10 10 ;=============================================================== ;Size : 29 bytes ;Speed : 347+3x cycles plus 1 if rounded down ; x is the number of set bits in the result. ;===============================================================
The only reason that I mention this is that I know a lot of graphical algorithms would have better results if the square root was returned in rounded form as opposed to just rounded up or down.
Wow, I just did something I didn't think was even possible. I found a good use for a forward djnz.
>.> Hehe, I use forward djnz in many-- if not most-- of my programs... It is one of the most useful tricks I use and is kind of my signature touch I use it to save time and memory a lot, especially in instances like this:
If I can, I will, but that will have to come in the future-- I still need to learn how to use the USB ports on an assembly level. If I can manage that, I will try to add some really cool functions that will make multiplayer game designing easier
Updates are great to hear. What was making the elixir difficult to work with? Was it simply because it was the first time you were working with an item to raise the PP (so you didn't have any other coding precedents)? In any case, nice work
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I wish I could help more, but most of the codes are a bit beyond my optimisation abilities.
