I am using LPC2148 with SIM800L on UART1 using interrupt. When I use memset(buff, 0 , sizeof(buff)); in line "75" at first the program works fine but when while(1) loop runs again it prints error over and over but when I comment the memset(buff, 0, sizeof(buff)); it works fine.
So why it is not receiving the data on using memset function?
code
#include <lpc214x.h> #include <stdio.h> #include <string.h> __irq void uart1_interrupt(void); void init_uart1(void); //////initialize uart1 void uart1_write(char data); //////send char on uart1 void uart1_send_string(char *str);//////send string on uart1 void Uart0_string(char *str); //////send string on uart0 void U0write(char data); //////send char on uart0 void init_uart0(void); //////initialize uart0 void pll_init(void); void timer_init(void); void delay_ms(unsigned int ms); //void clear_data(); /////clear buffer char buff[160]; //char sms_receive[60]; int i, a = 0; int main(void) { pll_init(); timer_init(); init_uart0(); //init_uart1(); VICVectAddr0 = (unsigned) uart1_interrupt; /////attach interrupt routine VICVectCntl0 = (1<<5)|7; ////enable uart irq slot for uart1 VICIntEnable |= (1<<7); ////enable uart1 interrupt VICIntSelect = 0x00000000; init_uart1(); Uart0_string("gsm test\r\n"); delay_ms(3000); while(1) { uart1_send_string("AT\r\n"); delay_ms(400); if(strstr(buff,"OK")) { Uart0_string(buff); } else { Uart0_string("ERROR "); } delay_ms(3000); uart1_send_string("AT+CNMI=?\r\n"); delay_ms(400); if(strstr(buff,"+CNMI")) { Uart0_string(buff); } else { Uart0_string("ERROR "); } delay_ms(3000); //clear_data(); memset(buff, 0 , sizeof(buff)); } } /*void clear_data() { for(i = 0; i<=sizeof(buff); i++) { buff[i] = 0; } }*/ __irq void uart1_interrupt(void) { buff[a] = U1RBR; a++; VICVectAddr = 0x00; } void init_uart1(void) { PINSEL0 = PINSEL0 | 0x00050000; ////UART1 pin selection U1LCR = 0x83; ////8 bit, no parity, 1 stop bit, DLAB - 1 U1DLL = 0x56; ////86 in decimal U1DLM = 0x00; U1FDR = 0xF2; U1LCR &= 0x0f; /////setting DLAB bit to 0 U1IER = 0x01; ////enable interrupt } void uart1_write(char data) { U1IER = 0x00; while(!(U1LSR &(1<<5))); ////U1LSR contains THRE status bit, wait while THR is empty U1THR = data; U1IER = 0x01; } void uart1_send_string(char *str) { U1IER = 0x00; while(*str != '\0') { uart1_write(*str++); } U1IER = 0x01; } /*char uart1_receive() { while(!(U1LSR & (1<<0))); return U1RBR; }*/ void init_uart0() { PINSEL0 = 0x00000005; ////selects TxD P0.0 and RxD P0.1 U0LCR = 0x83; ////8 bit, no parity 1 stop bit, DLAB = 1 U0DLL = 0x56; //// 86 in decimal U0DLM = 0x00; U0FDR = 0xF2; ////MULVAL and DIVADDVAL values U0LCR &= 0x0F; } void U0write(char data) { while(!(U0LSR & (1<<5))); ///////wait till THR is not empty U0THR = data; /////// write data to Transmit in U0THR } void Uart0_string(char *str) { while(*str != '\0') { U0write(*str++); } } void pll_init(void) { PLL0CON = 0x01; /////enable PLL//// PLL0CFG = 0x24; /////configure PLL///// PLL0FEED = 0xAA; //////feed sequence///// PLL0FEED = 0x55; //////feed sequence///// while(!(PLL0STAT & 0x00000400)); ///is locked//// PLL0CON = 0x03; ////connect PLL//// PLL0FEED = 0xAA; PLL0FEED = 0x55; //VPBDIV = 0x01; /////// PCLK = CCLK = 60MHz VPBDIV = 0x00; /////// PCLK = 60/4 = 15MHz } void timer_init(void) { //T0TCR = 0x00; T0CTCR = 0x0; ////selection of timer mode with every rising pclk edge T0PR = 14999; ////prescale register value will generate 1 ms at 60MHz T0TCR = 0x02; ////reset the timer counter and prescale couter } void delay_ms(unsigned int ms) { //T0TC = 0x00000000; T0TCR = 0x02; /////reset timer. Timer should be reset T0TCR = 0x01; /////enable timer to generate delay T0MR0 = ms; while(T0TC < T0MR0); /////wait until Timer counter register reaches desired delay T0TCR = 0x00; /////disable timer }
output when using "memset(buff, 0 , sizeof(buff))"
gsm test AT OK AT OK AT+CNMI=? +CNMI: (0-3),(0-3),(0,2),(0,1),(0,1) OK ERROR ERROR ERROR ERROR
output when not using memset funciton
gsm test AT OK AT OK AT+CNMI=? +CNMI: (0-3),(0-3),(0,2),(0,1),(0,1) OK AT OK AT+CNMI=? +CNMI: (0-3),(0-3),(0,2),(0,1),(0,1) OK AT OK AT OK AT+CNMI=? +CNMI: (0-3),(0-3),(0,2),(0,1),(0,1) OK AT OK AT+CNMI=? +CNMI: (0-3),(0-3),(0,2),(0,1),(0,1) OK AT OK AT+CNMI=? +CNMI: (0-3),(0-3),(0,2),(0,1),(0,1) OK AT OK AT+CNMI=? +CNMI: (0-3),(0-3),(0,2),(0,1),(0,1) OK AT OK