// simple test de laison Modbus Esclave vers Maitre PC // pour recuperer 3 mesures analogiques /* Exemple d’échange entre un maître et un esclave Trame émise par le maître : 01 03 00 02 00 01 25 CA - Adresse esclave : 01 - Code fonction 03 = lecture registre - N° du registre de début de lecture : MSB : 00 et LSB : 02 - Nombre de registre de lecture : MSB : 00 et LSB : 01 - CRC : 25 CA Réponse de l’esclave avec erreur : 01 83 02 01 31 - Adresse esclave : 01 - Code fonction : lecture avec MSB = 1 : 83 - Code erreur (n° registre) : 02 - CRC : 01 31 Réponse de l’esclave sans erreur : 01 03 02 02 58 B8 DE - Adresse esclave : 01 - Code fonction : lecture registre : 03 - Nombre d’octets données : 02 - Données du registre 0002 : MSB 02 et LSB : 58 - CRC : B8 DE Resultat avec Jbus_RTU.exe : Trame émise par le maître : >>1 3 0 1 0 3 54 0B reception: 02C3 0281 03AB */ #define LedBlanche PORTE.F0 #define SlaveAddress 1 //bank1 unsigned char buffer[32]; int Receive; int M0,M1,M2; unsigned short oj; char stop = 0; char *txt="MikroC 16F877 Modbus Q=10Mhz 19200 090606\n\r" ; char *p1="............................" ; char l; unsigned short int i,j,k; void Octet2Hex(char number); void octet_Bcd_to_2cars(short n); char CRC16(unsigned int dataLength,char check) ; char CheckRSInBuffer(void); unsigned char readRS(void); unsigned char ReadMBFrame(); unsigned char WriteMBFrame(); void Write_String(); void InitMain() { PORTA = 255; TRISA = 255; // PORTA is input PORTB = 0; // set PORTB to 0 TRISB = 0; // designate portb pins as output ADCON1=0b10001100 ; //RA0,RA1,RA2,RA5= ANA, RA3=+Vref, RE0..RE2=digital ,cadre a droite //ADCON1 = 0b10000101 ; // portA A0,A1=analog, A2=D, A3=+ref, A4,A5=digital PORTC = 0x0; // set PORTC to $FF TRISC = 0; // designate PORTC pins as output PORTE = 0x0; // set PORTE to $FF TRISE = 0; // designate PORTE pins as output } void Octet2Hex(char number) { char high,low; // high nibble high = ((number & 0xF0) >> 4) + 48; // + '0' if (high > 57u) high += 7; // > '9' // low nibble low = (number & 15u) + 48; // +'0' low nibble if (low > 57u) low += 7; // > '9' Usart_Write(high); Usart_Write(low); } //CRC 16 for modbus checksum rev PF june 2009 char CRC16(unsigned int dataLength,char check) { unsigned int CheckSum; unsigned int j; unsigned char lowCRC; unsigned char highCRC; unsigned short i; CheckSum = 0xffff; for (j=1; j<dataLength; j++) { CheckSum = CheckSum^(unsigned int)buffer[j]; for(i=8;i>0;i--) if((CheckSum)&0x0001) CheckSum = (CheckSum>>1)^0xa001; else CheckSum>>=1; } highCRC = CheckSum>>8; CheckSum<<=8; lowCRC = CheckSum>>8; if (check==1) { if ( (buffer[dataLength+1] == highCRC) & (buffer[dataLength] == lowCRC )) return 1; else return 0; } else { buffer[dataLength] = lowCRC; buffer[dataLength+1] = highCRC; return 1; } } char CheckRSInBuffer(void) { unsigned int j = 0; while((!RCIF) && (j < 30000)) j++; return RCIF; } unsigned char readRS(void) { while(!RCIF) continue; return RCREG; } unsigned char ReadMBFrame() { unsigned int counter = 0; unsigned int aux; stop = 0; while (!stop) if(!CheckRSInBuffer()) stop = 1; else { if (counter<=73) buffer[counter] = RCREG; counter++; } if ((buffer[1] == 16)&(((unsigned int) buffer[6] + 9)!=counter)) return 2; //wrong nr of registers if (counter > 32) return 2; //to many bytes in frame if (counter < 8) return 0; //to few bytes frame if (buffer[0] != SlaveAddress) return 0; //wrong address if ((buffer[1] != 3) & (buffer[1] != 16))return 1; //wrong modbus function aux = (unsigned int)buffer[2] * 256 + (unsigned int)buffer[3] + (unsigned int)buffer[4]*256 +(unsigned int)buffer[5]; if (aux > 8000) return 2; // to many registers if ((buffer[4]>0)|( buffer[5] > 32)) return 2; // to many registers if( CRC16(counter - 2,1)) return buffer[1]; //OK else return 0; //bad CRC } unsigned char WriteMBFrame() { unsigned int r =0; buffer[1] =1; //N° esclave buffer[2] =3; //code lecture mot buffer[3] =6; //nb de bytes buffer[4] =M0 / 256 ; //data 1 MSB buffer[5] =M0 % 256 ; //data 1 LSB buffer[6] =M1 / 256 ; //data 2 MSB buffer[7] =M1 % 256 ; //data 2 LSB buffer[8] =M2 / 256 ; //data 3 MSB buffer[9] =M2 % 256 ; //data 3 LSB buffer[10] =0; //CRC buffer[11] =0; //CRC r= CRC16(10,0) ; //met à jour CRC16 for (i=1;i<12;i++) Usart_Write(buffer[i]); return r ; } void Write_String() { short int i1,j1,k; j1=strlen(txt); i1=0; do { k=txt[i1]; Usart_Write(k); i1++; }while (i1<j1); } void main() { initMain(); USART_Init(19200); txt= strcpy(txt,"INIT usart 19200\n\r"); Delay_ms(1000); Write_String(); Usart_Write(13); Delay_ms(1000); i=0; while(1) { M0 = ADC_Read(0) ; LedBlanche=0; //txt= strcpy(txt,"Mesure ADC0= ");Write_String(); //WordToStr(M0, txt); Write_String(); //Usart_Write(13); /* to test CRC16 calcul buffer[1]=1; // num esclave buffer[2]=3; // requete=lecture mot buffer[3]=0;buffer[4]=35;// @ debut buffer[5]=0;buffer[6]=8;// nb de mots à lire buffer[7]=0;buffer[8]=0;// CRC16 Delay_ms(20); i=CRC16(7,0) ;//CRC 16 calcul must be 25CA txt= strcpy(txt,"CRC16= "); Write_String(); Usart_Write(9); Octet2Hex(buffer[7]); Usart_Write(9); Octet2Hex(buffer[8]); Usart_Write(13); */ Delay_ms(100); M1 = ADC_Read(1) ; Delay_ms(100); /* txt= strcpy(txt,"Mesure ADC1= "); Write_String(); WordToStr(M1, txt); Write_String(); Usart_Write(13); */ M2 = ADC_Read(4) ; LedBlanche =1; Delay_ms(800); if (Usart_Data_Ready()) { Receive=Usart_Read(); // Receive=readRS(); // if (Receive==1) // { // Receive=readRS(); // if (Receive==3) // { // Receive=readRS(); // if (Receive==1) // { // Receive=readRS(); // if (Receive==3) // { // Receive = readRS(); // Usart_Write(Receive); // Usart_Write(13); WriteMBFrame() ; // }; // }; // }; // }; }; } ; }