Serial-Communication.md

@@ -24,12 +24,12 @@ Other serial ports can be used as follows, but they have to be configured first.
 ```cpp
 #include <fcntl.h>
 //...
-fd=open("/dev/auxtty",O_RDWR);      //open serial port named auxtty
+int fd=open("/dev/auxtty",O_RDWR);      //open serial port named auxtty
 if(fd<0) printf("Cannot open /dev/auxtty");
 
 char buffer[11];         //Buffer is 10 chars + '\0'
-read(fd, 10, buffer);    //Read 10 chars
-write(fd, 10, buffer);   //Write 10 chars
+read(fd, buffer, 10);    //Read 10 chars
+write(fd, buffer, 10);   //Write 10 chars
 ```
 Pay attention to the baudrate at which the used port is set!