Tip's & Trick's...
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register swapping :
with Buffer : c=a / a=b / b=c - this swap the Reg. a <-> b - Buffer is 'c'
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with EXOR :
a = a^b
b = a^b
a = a^b
then a^b^a = b | ^ is bitwise EXOR
When in Reg.A the result of a EXOR linkup of two Var. ,and we now one of the Var.'s , we can recombined .
This is a thing most Kryptologic systems use.
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Increment a loopcounter with Z-reg. | on devices with the addiw Instruction you write :
adiw zlo,1
but what goes on when (Atiny15) don't have this instruction ?
subi ZL,-1 ; Increment Z by 1
sbci ZH,-1
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trigger a oscilloscope on I2C start ( or buy a Tektronix :-) )
The I2C start condition is SDA low while SCL is high, so we can make a little circuit of hardware.
The only thing we need is a D-latch.
SCL ------*D Q*------ out
SDA ----o>*C
connect the trigger to out and select Rising edge on the scope !
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change a Pot lin. <--> log.
register swapping :
with Buffer : c=a / a=b / b=c - this swap the Reg. a <-> b - Buffer is 'c'
---------------------
with EXOR :
a = a^b
b = a^b
a = a^b
then a^b^a = b | ^ is bitwise EXOR
When in Reg.A the result of a EXOR linkup of two Var. ,and we now one of the Var.'s , we can recombined .
This is a thing most Kryptologic systems use.
***********************************************************
Increment a loopcounter with Z-reg. | on devices with the addiw Instruction you write :
adiw zlo,1
but what goes on when (Atiny15) don't have this instruction ?
subi ZL,-1 ; Increment Z by 1
sbci ZH,-1
***********************************************************
trigger a oscilloscope on I2C start ( or buy a Tektronix :-) )
The I2C start condition is SDA low while SCL is high, so we can make a little circuit of hardware.
The only thing we need is a D-latch.
SCL ------*D Q*------ out
SDA ----o>*C
connect the trigger to out and select Rising edge on the scope !
**********************************************************
Init_Random: ;first time ldi TEMP,$AA ;Init the random number generator mov RAND1,TEMP ;since a 00,00,00 state will not mov RAND2,TEMP ;progress. mov RAND3,TEMP ;you can get a timer to pre load first time ret ********************************************************** simple 24bit random generator ********************************************************** simpler: rol RAND1 ;Shift the bits ->Carry rol RAND2 ;RAND are register or Ram rol RAND3 BRCC rr2 ldi TEMP,0x87 eor RAND1,TEMP rr2: ret *********************************************************
100 REM *********************** DEZHEX.BAS ************** 110 REM * Umwandlung von Dezimalzahlen in Hex-Zahlen * 120 REM ************************************************* 130 CLS 135 A$="0123456789ABCDEF" 140 PRINT "Von Dezimal zu Binär" 150 INPUT "DEZ = ";D 155 D$="" 170 M=D:D=INT(D/16) 180 M=M-D*16+1 190 D$=MID$(A$,M,1)+D$ 200 IF D > 0 THEN 170 210 IF LEN (D$) < 4 THEN D$ = "0" + D$: GOTO 210 220 PRINT "Hex = ";D$ 100 REM *********************** DEZBIN.BAS ******************* 110 REM * Umwandlung von Dezimalzahlen in Binärzahlen * 120 REM ****************************************************** 130 CLS 140 PRINT "Von Dezimal zu Binär" 150 INPUT "DEZ = ";D:B$="" 160 D = D/2 170 IF D = INT(D) THEN B$ = "0" + B$ 180 IF D <>INT(D) THEN B$ = "1" + B$ 190 D = INT(D) 200 IF D > 0 THEN 160 210 IF LEN (B$) < 8 THEN B$ = "0" + B$: GOTO 210 220 PRINT "BIN = ";B$ 100 REM *********************** HEXDEZ.BAS ******************* 110 REM * Umwandlung von Hex-Zahlen in Dezimalzahlen * 120 REM ****************************************************** 125 A$ = "0123456789abcdef" 130 CLS 140 PRINT "Hex zu Dezimal" 150 INPUT "Hex = ";H$ 160 L=LEN(H$):Y =-1:D=0 170 FOR I = L TO 1 STEP -1:X=0:Y=Y+1 180 X=X+1:IF MID$(A$,X,1)<>MID$(H$,I,1) THEN 180 190 D = D +(X - 1)*16^Y:NEXT I 200 PRINT "Dez = ";D