ROM-SPIM Delay between transmitted data bytes.

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by andypevy on Thu Apr 23 03:07:38 MST 2015

      I am using the demo ROM Based SPIM interrupt code to talk to a device.

I have set SPI0 up as follows :-

#define SPI_BITRATE  (15000000)

/* Set SPI transfer configuration */
  spimConfig.dXferBitRate = SPI_BITRATE;
  spimConfig.mode = ROM_SPI_CLOCK_CPHA0_CPOL0;
  spimConfig.lsbFirst = 0;
  spimConfig.dataBits = 8;
  spimConfig.PreDelay = 0;
  spimConfig.PostDelay = 0;
  spimConfig.FrameDelay = 0;
   spimConfig.TransferDelay = 1;

The MCU is running at 96MHz.

I am seeing a byte taking 580nS to be transmitted which I would expect,
however, I am then seeing a delay of 5.6uS before the next byte gets sent.

Is this what I should expect ?.

Is there any way of reducing the inter byte delay ?.