bool Gpio::setStateRange(int state, int startPin, int endPin)
{
if (!mInit){
fprintf(stderr, "GPIO not initialised\n");
return false;
}
int pwmVal;
if (state == 0)
pwmVal = 0;
else
pwmVal = 100000;
for (std::list<Gpio*>::iterator iter =
mOutputList.begin(); iter != mOutputList.end(); iter++)
{
Gpio *obj = *iter;
int pin = obj->getPin();
if (obj->getType() == OUT_PIN && pin >= startPin && pin <= endPin)
digitalWrite(obj->getPin(), state);
}
for (auto iter = mMonitorList.begin(); iter != mMonitorList.end(); iter++)
{
Gpio *obj = *iter;
int pin = obj->getPin();
if (obj->getType() == PWM && pin >= startPin && pin <= endPin){
if (mLastValue[pin] != pwmVal)
resetPwm(pin, pwmVal);
}
}
return true;
}
/**
* Start a thread to constantly monitor all the input pins we are
* interested in. When a state change is detected we store the
* time of the change. This creates a buffer so we can still see
* changes that happened a short time ago (so we don't miss any).
*
* It also writes PWM outputs and is responsible for writing random
* data, sine waves etc. to these outputs.
*/
bool Gpio::startMonitor()
{
if (!mInit){
fprintf(stderr, "GPIO not initialised\n");
return false;
}
// Do we have anything to monitor?
if (mMonitorList.size() == 0)
return true;
bool usingPwm = false;
for (auto iter = mMonitorList.begin(); iter != mMonitorList.end(); iter++)
{
Gpio *obj = *iter;
int pin = obj->getPin();
if (obj->getType() == PWM){
// Don't start outputting PWM until we execute a relevant command
mMonType[pin] = INACTIVE;
mMonMutex[pin] = PTHREAD_MUTEX_INITIALIZER;
// Set to full range initially (range map is in millis)
mRangeMapMin[pin] = 0;
mRangeMapMax[pin] = 100000;
usingPwm = true;
}
else {
// Input pins are always monitored
initMonitorInput(pin);
}
}
if (usingPwm){
// Start ServoBlaster. We use this instead of hardware
// PWM as there is only one hardware PWM pin on the Pi
// and hardware PWM interferes with analog audio.
if (!startServoBlaster())
return false;
}
// Start monitor thread
if (pthread_create(&mMonitorId, NULL, monitor, NULL) != 0){
fprintf(stderr, "** Failed to start gpio monitor\n");
return false;
}
// Wait for monitor to start
for (int retries = 0; retries < 15; retries++){
if (mMonitorRunning)
return true;
Engine::sleep(200);
}
printf("** Failed to start gpio monitor\n");
return false;
}
bool Gpio::startServoBlaster()
{
// Stop ServoBlaster if it's already running
mServoBlasterPid = Engine::findProcess(SB_COMMAND);
if (mServoBlasterPid != -1)
stopServoBlaster();
if (Engine::displayOn)
printf("Starting ServoBlaster (%s)\n", SB_COMMAND);
mServoBlasterPid = fork();
if (mServoBlasterPid == -1){
fprintf(stderr, "** Failed to create ServoBlaster process\n");
return false;
}
if (mServoBlasterPid != 0){
// This is the parent process
// Make sure ServoBlaster started
int status;
for (int retries = 0; retries < 15; retries++){
if (waitpid(mServoBlasterPid, &status, WNOHANG) != -1){
sleep(1);
mServoBlasterOut = open(SB_DEVICE, O_WRONLY|O_SYNC);
if (mServoBlasterOut == -1){
fprintf(stderr, "** Failed to open %s\n", SB_DEVICE);
return false;
}
return true;
}
Engine::sleep(200);
}
fprintf(stderr, "ServoBlaster failed to start\n");
return false;
}
// Make ServoBlaster use same pin mapping as wiringPi.
// We are mapping wiringPi pin number to physical pin number.
const int pinMap[] = {11,12,13,15,16,18,22,7,3,5,24,26,19,21,23,8,10};
int servoBlasterPin[MAX_PWM_PINS];
// ServoBlaster needs to know which pins we are using for PWM
for (int i = 0; i < MAX_PWM_PINS; i++)
servoBlasterPin[i] = 0;
for (auto iter = mMonitorList.begin(); iter != mMonitorList.end(); iter++)
{
Gpio *obj = *iter;
if (obj->getType() == PWM){
int pin = obj->getPin();
servoBlasterPin[pin] = pinMap[pin];
}
}
// First arg is the pin list
char argv1[256];
sprintf(argv1, "--p1pins=%d", servoBlasterPin[0]);
char addStr[64];
for (int i = 1; i < MAX_PWM_PINS; i++){
sprintf(addStr, ",%d", servoBlasterPin[i]);
strcat(argv1, addStr);
}
// Second arg is the cycle time
char argv2[256];
sprintf(argv2, "--cycle-time=%dus", SB_CYCLE_TIME);
const char *argv[16];
argv[0] = SB_COMMAND;
argv[1] = argv1;
argv[2] = argv2;
for (int i = 0;; i++){
argv[i+3] = SB_PARAMS[i];
if (SB_PARAMS[i] == NULL)
break;
}
// redirect stdout and stderr
freopen("/tmp/servoblaster.log", "w", stdout);
freopen("/tmp/servoblaster.log", "w", stderr);
// Try from current dir first
char command[256];
sprintf(command, "./%s", SB_COMMAND);
execv(command, (char* const*)argv);
// execv only returns if an error occurs
// Now try from PATH
execvp(SB_COMMAND, (char* const*)argv);
// execv only returns if an error occurs
fprintf(stderr, "** Failed to start ServoBlaster using command:\n");
fprintf(stderr, "%s", SB_COMMAND);
for (int i = 0; argv[i] != NULL; i++)
fprintf(stderr, " %s", argv[i]);
fprintf(stderr, "\n");
return true;
}
