/* USART pinmux initialization function. 
Set each required pin to USART functionality  */
void TARGET_IO_PORT_init()
/* USART pinmux initialization function. 
Set each required pin to USART functionality  */
void TARGET_IO_PORT_init()
{
	gpio_set_pin_function(PA21, MUX_PA21A_USART1_RXD1);
	gpio_set_pin_function(PB4, MUX_PB4D_USART1_TXD1);
}