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CPI emulationI'm currently writing Sinclairean's emulation assembly for the CPI/CPD/CPIR/CPDR instruction group. Does anybody know what exactly the behavior of th…
... 's emulation assembly for the CPI/CPD/CPIR/CPDR instruction group ... -
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 …
... concepts (jumps, flow control, routines, CPI):
[code]searchmem
search: cpi ; a-(HL)
jr z ... -
Machine Code ChallengeHere's a challenge for all you Z80 programmers. Points to be awarded for elegance and brevity. (I haven't got the solution either) HL addresses the …
... no reset bits.
Skip CPI ; Zero flag reset when a ... -
Machine Code ChallengeHere's a challenge for all you Z80 programmers. Points to be awarded for elegance and brevity. (I haven't got the solution either) HL addresses the …
... .
8013 EDA1 16 Skip CPI ; Zero flag reset when a ... -
MEMPTR finally crackedThis post is mainly for emulator developers. As you may be well know there is a misterious internal register in Z80 CPU (MEMPTR) which value is set …
... it earlier). E.g.:
CPI: MSB of ALU16_01+1
in our case:
CPI: MEMPTR++
CPD: MEMPTR-- (in ... -
MEMPTR finally crackedThis post is mainly for emulator developers. As you may be well know there is a misterious internal register in Z80 CPU (MEMPTR) which value is set …
... it earlier). E.g.:
CPI: MSB of ALU16_01+1
in our case:
CPI: MEMPTR++
CPD: MEMPTR-- (in ... ; it must be read as CPI: MSB of (ALU16_01+1). There ... -
finding largest value (z80 assembly)suppose we have to write z80 program which requires to find the biggest value in a block of memory starts from the address 101h until address stored …
[QUOTE=GOC]Hint: use CPIR.[/QUOTE]
Well CPI anyway. There, now we've given away 1/9 lines of the solution. -
finding largest value (z80 assembly)suppose we have to write z80 program which requires to find the biggest value in a block of memory starts from the address 101h until address stored …
the algorithm is as follows - in psuedo code :-)
load hl with the start of the block to search
load bc with the length of the block to search
load accumulator with value pointed to by hl (ie. the current smallest number)
loop ... -
finding largest value (z80 assembly)suppose we have to write z80 program which requires to find the biggest value in a block of memory starts from the address 101h until address stored …
[QUOTE=Kiwi]the algorithm is as follows - in psuedo code :-)
load hl with the start of the block to search
load bc with the length of the block to search
load accumulator with value pointed to by hl (ie. the current smallest number ... -
finding largest value (z80 assembly)suppose we have to write z80 program which requires to find the biggest value in a block of memory starts from the address 101h until address stored …
... teacher wants you to use CPI to show how clever you ... though that a version without CPI might be a touch faster ... -
ZXLFN - storing tape header in a long file nameHi lads ;) Couple of months ago, the group of guys interested in divIDE software development has came up with an interesting idea - store tape heade…
The new GP2Xpectrum releases threadYeah, I know the thread title isn't exactly too original, but I've decided that just one post to hold all updates makes more sense than a lot of smal…
ZXSpin 0.61 Available nowHi all! Well, after a lengthy few testing cycles, I'm taking the plunge and uploading the latest version of ZXSpin, to replace the rather aged old 0…
... Spectaculator 5.3 fails in cpi, cpd and the group ( I ... ,(+1)
bit n,
cpi
And I ...Project: M.u.l.e.Wokani came up with a great idea about trying an open-development approach for spectrum games, and I thought why not try with a game I have under dev…
... .users.on.net/~tonyt73/SevenuPImageParser.cpi[/url] and place into the ...TommyGun 0.9.x updates** Should be available via the utilities page soon! Please be patient :-) ** I'll be posting all future updates in this thread, instead of creating …
Machine code help pls: LDI example[deleted]
... [/quote]
Nope, a CPI instruction only sets/resets the ... like, you can think of CPI as internally doing a DEC ... that that's the way CPI works...)Machine code help pls: LDI example[deleted]
... though, this time regarding CPI ...
CPI compares A with (HL ... bytes long:
Search CPI
JR Z, Found
By heart,
CPI set Z if A=(HL ... can do this
CPI
JR Z,AISHL
Machine code help pls: LDI example[deleted]
... BEEP;320895]By heart,
CPI set Z if A=(HL ... can do this
CPI
JR Z,AISHL
yup,
LDI/LDD
CPI/CPD
are same ...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 …
... concepts (jumps, flow control, routines, CPI):
[code]searchmem
search: cpi ; a-(HL)
jr z ...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 …
... at address 0
search: cpi ; a-(HL)
jr z ...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 …
CPI and friends affect the parity ... .
[code]
search: cpi ; a-(HL)
jr z ...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 …
... for 0. reset flags
cpi ; a-(HL)
jr z ... the entire memory
.search cpi ; a-(HL)
jr z ...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 …
It's worth mentioning that CPI doesn't have to be ... something useful here!
cpi ;HL = HL + 1, BC = BC ... /> In the second routine the CPI isn't being used in ...
