Starts UARTF data reception.
Remark 1. This API function performs byte-level UARTF reception the number of times specified by the argument rx_num, and stores the data in the buffer specified by the argument rx_buf.
Remark 2. Actual UARTF reception starts after this API function is called, and R_UARTFn_Start is then called.
Remark 
3.      If the asynchronous serial interface LIN-UART 
(UARTF) is used in expansion bit mode, then the received data is stored in the 
buffer specified by argument rx_buf, in the following format.
"8-bit 
data", "Expansion bit", "8-bit data", "Expansion bit", ...
[Syntax]
#include “r_cg_macrodriver.h”
MD_STATUS R_UARTF_Receive ( uint8_t * const rx_buf, uint16_t rx_num );
Remark n is the channel number.
[Argument(s)]
| 
       I/O  | 
    
       Argument  | 
    
       Description  | 
| 
       O  | 
    
       uint8_t * const rx_buf;  | 
    
       Pointer to a buffer to store the received data  | 
| 
       I  | 
    
       uint16_t rx_num;  | 
    
       Total amount of data to receive  | 
[Return value]
| 
       Macro  | 
    
       Description  | 
| 
       MD_OK  | 
    
       Normal completion  | 
| 
       MD_ARGERROR  | 
    
       Invalid argument specification  |