Content originally posted in LPCWare by sreejugr on Wed Jul 29 02:41:32 MST 2015
Hello,
I'm using LPC 3250 Developer's Kit. I want to study the UART 5 with the TX interrupt enabled. Here is the piece of c code compiled using RVDS and debugged using DSTREAM.
The program is transmitting the characters to hyper terminal but I was expecting the character 'I' to be transmitted when it enters the IRQ ISR. But it didn't.
Need your assistance to generate interrupt in IRQ mode for UART 5 Transmission.
Thank You
S GR
#include "lpc32xx_uart.h"
#include "lpc32xx_timer.h"
#include "lpc32xx_chip.h"
/****************************************************************************************
*Function :send_data
*Inputs :string
*Output :none
*Purpose :To print the string on serial port
****************************************************************************************/
void send_data(unsigned char ch)
{
UartReg.dll_fifo=ch;
while(!(UartReg.lsr & 0x20));
}
/****************************************************************************************
*Function :send_data
*Inputs :string
*Output :none
*Purpose :To print the string on serial port
****************************************************************************************/
void send_string(volatile unsigned char *str)
{
while(*str != '\0')
{
send_data(*str);
str++;
}
}
/****************************************************************************************
*Function :receive_data
*Inputs :string
*Output :none
*Purpose :To print the string on serial port
****************************************************************************************/
unsigned char receive_data(void)
{
unsigned char ch;
while(!(UartReg.lsr & 0x01));
ch=UartReg.dll_fifo;
return(ch);
}
/****************************************************************************************
*Function :uart5_MICInit
*Inputs :
*Output :
*Purpose :
****************************************************************************************/
void uart5_MICInit(void)
{
UartReg.dlm_ier = UART_IER_THRE; // Enable UART Tx Interrupt
MIC_APR |= (1<<9); // Activation Polarity (Active High for UART 5)
MIC_ATR &= ~(1<<9); // Activation Type (Level 0)
MIC_ITR &= ~(1<<9); // Interrupt Type (IRQ = 0)
MIC_ER |= (1<<9); // Enable register for UART 5
}
int main(void)
{
uart5_MICInit();
send_string((unsigned char *)"UART5 LPC3250 \n\r");
while(1)
{
ch = receive_data();
send_data(ch);
}
return 1;
}
__irq void IRQ_Handler(void)
{
send_data('I'); // for uart5
return;
}
