tmk_core/tool/mbed/mbed-sdk/libraries/tests/libs/SPIHalfDuplex/SPIHalfDuplex.cpp

   1 /* mbed Microcontroller Library - SPIHalfDuplex
   2  * Copyright (c) 2010-2011 ARM Limited. All rights reserved.
   3  */
   4 #include "SPIHalfDuplex.h"
   5
   6 #if DEVICE_SPI
   7
   8 #include "spi_api.h"
   9 #include "pinmap.h"
  10
  11 #define GPIO_MODE 0
  12 #define SPI_MODE  2
  13
  14 namespace mbed {
  15
  16 SPIHalfDuplex::SPIHalfDuplex(PinName mosi, PinName miso, PinName sclk) : SPI(mosi, miso, sclk) {
  17     _mosi = mosi;
  18     _miso = miso;
  19     _sbits = _bits;
  20 }
  21
  22 void SPIHalfDuplex::slave_format(int sbits) {
  23     _sbits = sbits;
  24 }
  25
  26 int SPIHalfDuplex::write(int value) {
  27     int t_bits = _bits;
  28     pin_function(_mosi, SPI_MODE);
  29     int ret_val = SPI::write(value);
  30     if (ret_val != value) {
  31         return -1;
  32     }
  33     format(_sbits, _mode);
  34     pin_function(_mosi, GPIO_MODE);
  35     ret_val = SPI::write(0x55);
  36     format(t_bits, _mode);
  37     pin_function(_mosi, SPI_MODE);
  38     return ret_val;
  39 }
  40
  41 } // end namespace mbed
  42
  43 #endif