Restart 18F2620

[cerio]

I ask aid, I do not know English well. Use PBP2.46 and MPLAB v7.50 the circuit works well with 16F876. The connected PIC to Wawecom Q2501ed to the PC. They are passed to the 18F2640. The program from time to time restart and I do not understand the cause, as it is made has to find the cause of the restart? I enclose the SW and the rows 18F2620.INC modified. Salutes to all thanks
Report PC
Fine Inizializzazione
StatoQ2501 OK
Tensione= 3,377
GestioneS�S <---- non corrected ?
StatoQ2501 OK
Tensione= 3,377
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Tensione= 3,377
GestioneSMS
StatoQ2501 OûStartup Startup <---- SW restart
Fine controllo RTS/CTS
Rete GSM OK
CBST OK
Fine Inizializzazione
StatoQ2501OK
Tensione= 3,377
GestioneSMS
3StatoQ2501 OK <---- non corrected ?
Tensione= 3,377
GestioneSMS
StatoQ™501 OK <---- non corrected ?

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GestµoneSMS <---- non corrected ?
StatoQ2501 OK
Tensione= 3,377
GestioneSMS
StaStartup Startup <---- SW restart
Fine controllo RTS/CTS
Rete GSM OK
CBST OK
Fine Inizializzazione
StatoQ2501 OK
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