How to read and write the data to the external flash

[ps_anu]

Hi... 

How to read and write to the external flash 

I am using sdk 15.2 version, interfacing the  development kit nRF52832  with w25q64 external flash via spi. I have read the datasheet of external flash using the address I am trying to read the data from flash but I couldn't able to read. I am not getting anydata on the terminal  . I am using spi example. Which function I should use to read the data from external flash, where I should I pass the address too. I don't know where to pass the address, m_tx_buffer[] ="0x03h" ;  Is it correct or wrong?? Suggest me please. This is the first time I am working on spi 

[ps_anu]

I am getting the ff value in rx_buffer . i am receiving ff value. Even i set the delay command between the write and read . I am writing the string 

#define TEST_STRING "Z" //"Nordic"
static uint8_t m_tx_buf[] = TEST_STRING;