/*Write thread. Reads messages from UDP socket and sends them to the J1708 bus.*/
void * WriteThread(void* args){
int gpio;
int len;
int len2;
char msg_buf[256];
char read_buf[256];
int client_size = sizeof(other_addr);
int sent;
struct timespec sleepspec;
sleepspec.tv_sec = 0;
sleepspec.tv_nsec = BIT_TIME*10;
useconds_t sleeptime;
// gpio = open_gpio("/sys/class/gpio/gpio60/value");
while(1){
len = recvfrom(read_socket,msg_buf,256,0,(struct sockaddr *) &other_addr, &client_size);
sleeptime = BIT_TIME_MICROS*12*len;
sent = 0;
// printf("%s\n","Sending to ecm serial");
// ppj1708(len,msg_buf);
while(!sent){
wait_for_quiet(gpio,6,&buslock);
//fprintf(stderr,"sending a message!\n");
write(fd,msg_buf,len);
//Wait for the UART to finish sending the message onto the bus.
usleep(sleeptime);
/* Read the message back. If we don't do this, it will be read by the read thread.
* This also helps collision detection.
*/
len2 = read(fd,&read_buf,len);
// printf("%s","ECM cleared from message buffer: ");
// ppj1708(len2,read_buf);
/* Quick and dirty collision detection.
* Compare data read back from the bus with the data that we tried to send.
* If they're different, we know that there was a collision. Retry until success.
*/
if(!memcmp(msg_buf,read_buf,len)){
sent = 1;
}else{
pthread_mutex_unlock(&buslock);
}
}
pthread_mutex_unlock(&buslock);
nanosleep(&sleepspec,NULL);
}
}
void * WriteThread(void* args){
int gpio;
int len;
int len2;
char msg_buf[256];
char read_buf[256];
int client_size = sizeof(other_addr);
int sent;
struct timespec sleepspec;
sleepspec.tv_sec = 0;
sleepspec.tv_nsec = BIT_TIME*10;
useconds_t sleeptime;
// gpio = open_gpio("/sys/class/gpio/gpio60/value");
while(1){
len = recvfrom(read_socket,msg_buf,256,0,(struct sockaddr *) &other_addr, &client_size);
sleeptime = BIT_TIME_MICROS*12*len;
sent = 0;
// printf("%s\n","Sending to ecm serial");
// ppj1708(len,msg_buf);
while(!sent){
wait_for_quiet(gpio,6,&buslock);
//fprintf(stderr,"sending a message!\n");
write(fd,msg_buf,len);
usleep(sleeptime);
len2 = read(fd,&read_buf,len);
printf("%s","ECM cleared from message buffer: ");
ppj1708(len2,read_buf);
if(!memcmp(msg_buf,read_buf,len)){
sent = 1;
}else{
pthread_mutex_unlock(&buslock);
}
}
pthread_mutex_unlock(&buslock);
nanosleep(&sleepspec,NULL);
}
}
