questo è lo sketch che ho caricato su arduino, è quello che si trova all'interno del toolbox scaricato dal sito di mathworks.
In questo caso non programmo da arduino ma direttamente da matlab!
/* define internal for the MEGA as 1.1V (as as for the 328) */
#if defined(AVR_ATmega1280) || defined(AVR_ATmega2560)
#define INTERNAL INTERNAL1V1
#endif
void setup() {
/* Make sure all pins are put in high impedence state and
that their registers are set as low before doing anything.
This puts the board in a known (and harmless) state /
int i;
for (i=0;i<20;i++) {
pinMode(i,INPUT);
digitalWrite(i,0);
}
/ initialize serial */
Serial.begin(115200);
}
void loop() {
/* variables declaration and initialization */
static int s = -1; /* state /
static int pin = 13; / generic pin number */
int val = 0; /* generic value read from serial /
int agv = 0; / generic analog value /
int dgv = 0; / generic digital value */
/* The following instruction constantly checks if anything
is available on the serial port. Nothing gets executed in
the loop if nothing is available to be read, but as soon
as anything becomes available, then the part coded after
the if statement (that is the real stuff) gets executed */
if (Serial.available() >0) {
/* whatever is available from the serial is read here */
val = Serial.read();
/* This part basically implements a state machine that
reads the serial port and makes just one transition
to a new state, depending on both the previous state
and the command that is read from the serial port.
Some commands need additional inputs from the serial
port, so they need 2 or 3 state transitions (each one
happening as soon as anything new is available from
the serial port) to be fully executed. After a command
is fully executed the state returns to its initial
value s=-1 */
switch (s) {
/* s=-1 means NOTHING RECEIVED YET ******************* */
case -1:
/* calculate next state /
if (val>47 && val<90) {
/ the first received value indicates the mode
49 is ascii for 1, ... 90 is ascii for Z
s=0 is change-pin mode
s=10 is DI; s=20 is DO; s=30 is AI; s=40 is AO;
s=90 is query script type (1 basic, 2 motor)
s=340 is change analog reference
/
s=10(val-48);
}
/* the following statements are needed to handle
unexpected first values coming from the serial (if
the value is unrecognized then it defaults to s=-1) */
if ((s>40 && s<90) || (s>90 && s!=340)) {
s=-1;
}
/* the break statements gets out of the switch-case, so
/* we go back to line 97 and wait for new serial data /
break; / s=-1 (initial state) taken care of */
/* s=0 or 1 means CHANGE PIN MODE */
case 0:
/* the second received value indicates the pin
from abs('c')=99, pin 2, to abs('t')=116, pin 19 /
if (val>98 && val<117) {
pin=val-97; / calculate pin /
s=1; / next we will need to get 0 or 1 from serial /
}
else {
s=-1; / if value is not a pin then return to -1 /
}
break; / s=0 taken care of */
case 1:
/* the third received value indicates the value 0 or 1 /
if (val>47 && val<50) {
/ set pin mode /
if (val==48) {
pinMode(pin,INPUT);
}
else {
pinMode(pin,OUTPUT);
}
}
s=-1; / we are done with CHANGE PIN so go to -1 /
break; / s=1 taken care of */
/* s=10 means DIGITAL INPUT ************************** */
case 10:
/* the second received value indicates the pin
from abs('c')=99, pin 2, to abs('t')=116, pin 19 /
if (val>98 && val<117) {
pin=val-97; / calculate pin /
dgv=digitalRead(pin); / perform Digital Input /
Serial.println(dgv); / send value via serial /
}
s=-1; / we are done with DI so next state is -1 /
break; / s=10 taken care of */
/* s=20 or 21 means DIGITAL OUTPUT ******************* */
case 20:
/* the second received value indicates the pin
from abs('c')=99, pin 2, to abs('t')=116, pin 19 /
if (val>98 && val<117) {
pin=val-97; / calculate pin /
s=21; / next we will need to get 0 or 1 from serial /
}
else {
s=-1; / if value is not a pin then return to -1 /
}
break; / s=20 taken care of */
case 21:
/* the third received value indicates the value 0 or 1 /
if (val>47 && val<50) {
dgv=val-48; / calculate value /
digitalWrite(pin,dgv); / perform Digital Output /
}
s=-1; / we are done with DO so next state is -1 /
break; / s=21 taken care of */
/* s=30 means ANALOG INPUT *************************** */
case 30:
/* the second received value indicates the pin
from abs('a')=97, pin 0, to abs('f')=102, pin 6,
note that these are the digital pins from 14 to 19
located in the lower right part of the board /
if (val>96 && val<103) {
pin=val-97; / calculate pin /
agv=analogRead(pin); / perform Analog Input /
Serial.println(agv); / send value via serial /
}
s=-1; / we are done with AI so next state is -1 /
break; / s=30 taken care of */
/* s=40 or 41 means ANALOG OUTPUT ******************** */
case 40:
/* the second received value indicates the pin
from abs('c')=99, pin 2, to abs('t')=116, pin 19 /
if (val>98 && val<117) {
pin=val-97; / calculate pin /
s=41; / next we will need to get value from serial /
}
else {
s=-1; / if value is not a pin then return to -1 /
}
break; / s=40 taken care of */
case 41:
/* the third received value indicates the analog value /
analogWrite(pin,val); / perform Analog Output /
s=-1; / we are done with AO so next state is -1 /
break; / s=41 taken care of */
/* s=90 means Query Script Type (1 basic, 2 motor) /
case 90:
if (val==57) {
/ if string sent is 99 send script type via serial /
Serial.println(1);
}
s=-1; / we are done with this so next state is -1 /
break; / s=90 taken care of */
/* s=340 or 341 means ANALOG REFERENCE *************** */
case 340:
/* the second received value indicates the reference,
which is encoded as is 0,1,2 for DEFAULT, INTERNAL
and EXTERNAL, respectively */
switch (val) {
case 48:
analogReference(DEFAULT);
break;
case 49:
analogReference(INTERNAL);
break;
case 50:
analogReference(EXTERNAL);
break;
default: /* unrecognized, no action */
break;
}
s=-1; /* we are done with this so next state is -1 /
break; / s=341 taken care of */
/* ******* UNRECOGNIZED STATE, go back to s=-1 ******* */
default:
/* we should never get here but if we do it means we
are in an unexpected state so whatever is the second
received value we get out of here and back to s=-1 */
s=-1; /* go back to the initial state, break unneeded */
} /* end switch on state s */
} /* end if serial available */
} /* end loop statement */
