spi buffer p_tx_data

[sslap]

I'm trying to setup a rather straight-forward SPI communication with a LIS2DH. For this I use the NRF51422 on a PCA10003 board. I have started with the spi_master_example for the NRF51422 on a NRF6310 board. I guess this can also work on the PCA10003 board by just changing some pins in the configuration (Or is this wrong).

However I have a problem with the p_tx_data buffer.

If for example i would like to send 2 bytes after each other say m_tx_data[2]:

                  m_tx_data[0] = 160;    
                  m_tx_data[1] = 95;
                  spi_send_recv(m_tx_data, m_rx_data, TX_RX_BUF_LENGTH);

In the function spi_send_recv, and all following function in this, it always only tries to send the first byte. Although in the reference manuel is said that it could send two bytes.

I could ofcourse first send the first byte of m_tx_data and then the second but these two bytes have to follow eachother without having a clock cycle of SCK between eachother (the first byte is the adress and the second byte is the message to send)

Is there something rong with the example or can I send the two bytes after eachother without an clock cycle SCK between?

Thanks a lot!!

[John]

Are you sure that it is the SCK that you do not want to toggle between bytes rather than the SS (Slave Select)? As I understand SPI the clock has to toggle on every bit transmitted. Wikipedia has a decent high level overview of SPI:

SPI explained

[sslap]

I meant that the two bytes have to be send likeif they were a 16-bit number. If SCK would make a cycle or even only a part it would be recognized by the slave as a zero.

So I just need to send a 16-bit message without introducing an error or pause between the two 8-bit messages.