void spi0::setClockDiv(int factor)//8<=factor <=255
{
disableCS();
if(factor<8)factor=8; //make sure factor is always greater than 8
clkDiv=factor&(~0x1); //save with lsb always 0
S0SPCCR=clkDiv; //number of pclk cycles that
clock=pclk/clkDiv;
//make up one spiclock cycle
}
uint8_t gpio_MCP23SXX::beginSpi(bool avoidSpiInit)
{
uint8_t _initError = 0xFF;
#if defined(__MK20DX128__) || defined(__MK20DX256__)//Teensy 3.0 -> 3.2
if ((_mosi == 11 || _mosi == 7) && (_sclk == 13 || _sclk == 14) && (_miso == 255 || _miso == 12 || _miso == 8)) {
if (!avoidSpiInit) SPI.begin();
SPI.setMOSI(_mosi);
if (_miso != 255) SPI.setMISO(_miso);
SPI.setSCK(_sclk)
if (SPI.pinIsChipSelect(_cs)){
pinMode(_cs,OUTPUT);
disableCS();
} else {
bitClear(_initError,1);
}
} else {
/*
Return register content from bank A & B of a 16 bit GPIO chip,
combined in a 16 bit data. An 8 Bit chip will return always bank A.
Parameters
reg: a legal 8bit MCP23Sxx register.
*/
uint16_t gpio_MCP23SXX::gpioReadRegisterBoth(byte reg)
{
if (_ports < 16){
return gpioReadRegister(reg);
} else {
uint16_t result = 0;
#if defined(SPI_LEGACY_METHOD)
startTransaction();
writeByte_cont(_readCmd);
writeByte_cont(reg);
#if defined(SPI_HAS_TRANSACTION)
setSpiSettings(SPISettings(10000000, MSBFIRST, SPI_MODE0));
result = readWord_cont();
setSpiSettings(SPISettings(_maxGpioSPIspeed, MSBFIRST, SPI_MODE0));
#else
result = readWord_cont();
#endif
disableCS();
endTransaction();
#else
_spi.startTransaction();
_spi.writeByte_cont(_readCmd);
_spi.writeByte_cont(reg);
#if (defined(__MK20DX128__) || defined(__MK20DX256__) || defined(__MK64FX512__) || defined(__MK66FX1M0__))
_spi.waitTransmitComplete();
#endif
#if defined(SPI_HAS_TRANSACTION)
_spi.setSpiSettings(SPISettings(10000000, MSBFIRST, SPI_MODE0));
result = _spi.readWord_cont(false);//command mode
_spi.setSpiSettings(SPISettings(_maxGpioSPIspeed, MSBFIRST, SPI_MODE0));
#else
result = _spi.readWord_cont(false);//command mode
#endif
#if (defined(__MK20DX128__) || defined(__MK20DX256__) || defined(__MK64FX512__) || defined(__MK66FX1M0__))
_spi.writeByte_last(0xFF);//NOP?
#else
_spi.disableCS();
#endif
_spi.endTransaction();
#endif
return result;
}
}
