NRF9E5 read string from UART

[Lockdog]

Hello! I need to read a string from UART, there's code below:

unsigned char GetChar(void)
{
    while(!RI)
        ;
    RI = 0;
    return SBUF;
}

int Readfstr(void)
{
	  char first_s, last_s;
		unsigned short int i=0;
		first_s = GetChar();
			if (first_s=='m') 
				{
					uart_buf[i] = first_s;
						while (last_s!='E')
						{
							i++;
							last_s = GetChar();
							uart_buf[i]=last_s;
						}
						return 1;	
				} else return 0;
}

But it doesn't work

[Øyvind Karlsen]

Hi,

Have you set port 01 and 02 to RXD and TXD by writing?

P0_ALT.1 = 1; //Set P01 to RXD
P0_ALT.2 = 1; //Set P02 to TXD

The direction of UART RXD also depends on the setting of P0_DIR.1 (should be set to 1 for input).

Best regards,

Øyvind

[Øyvind Karlsen]

You should clear RI before the while loop in GetChar. The REN bit should also be set before clearing RI, and cleared after the while loop.