I'm trying to receive data from a electronic compass in simulink. The compass sends data using the NMEA protocol through USB using a serial connection. The serial output format is: 4800 baud, 8 data bits, 1 stop bit, no parity and uses the following sentences: $HCHDG,hhh.h,,,,*ssss<CR><LF> The only info I need is the heading (so the hhh.h number in the sentence above). I try using the serial block (serial configuration and serial read) but this only gives me zeroes when trying to read. Any suggestions how to get this into simulink? In matlab it goes perfectly, with fopen( ) and then fscanf( ).