Starts SCI master transmission (simple SPI mode).
Remark 1. This API function repeats the byte-level SCI master transmission from the buffer specified in argument tx_buf the number of times specified in argument tx_num.
Remark 2. When performing a SCI master transmission, R_SCIn_Start must be called before this API function is called.
[Syntax]
#include "r_cg_macrodriver.h"
MD_STATUS R_SCIn_SPI_Master_Send ( uint8_t * const tx_buf, uint16_t tx_num );
Remark n is the channel number.
[Argument(s)]
| 
       I/O  | 
    
       Argument  | 
    
       Description  | 
| 
       I  | 
    
       uint8_t * const tx_buf;  | 
    
       Pointer to a buffer storing the transmission data  | 
| 
       I  | 
    
       uint16_t tx_num;  | 
    
       Total amount of data to send  | 
[Return value]
| 
       Macro  | 
    
       Description  | 
| 
       MD_OK  | 
    
       Normal completion  | 
| 
       MD_ARGERROR  | 
    
       Invalid argument tx_num specification  |