Take UTC time from NMEA format.

[jjs0713]

Hi, Everyone !
I made a C program. I want to know serial communication at micom which is
ATMEL 89C52.
It's received to micom RX pin(serial comm.) NMEA format from some set.
I'd like to take UTC Time. then I'll display to LCD output.
I really need to help which is to get UTC time from NMEA format.

1. NMEA format

$GPGGA,000915.5,3727.85245,N,12702.53467,E,0,00,,684.6,M,18.5,M,,*71
$GPGSA,A,1,,,,,,,,,,,,,,,*1E
$GPGSV,1,1,00,,,,,*55
$GPRMC,000915.5,V,3727.85245,N,12702.53467,E,00.0,090.0,020902,,,N*44
$GPVTG,090.0,T,,M,00.0,N,00.0,K*69

Above, It's UTC time("000915.5") Next to "$GPGGA,".

2. Remark
-. 4800 Baud Rate
-. Data bit : 8Bit
-. Parity : None
-. Stop bit : 1

I need to your help. pls...
sorry! My English skill is not so good.
If you have any question, just send E-mail to me.
Thanks a lot.