#define CS_DEASSERT GPIOC->BSRRL = GPIO_Pin_4 //GPIO_SetBits(GPIOC, GPIO_Pin_4)
#define CS_ASSERT GPIOC->BSRRH = GPIO_Pin_4 //GPIO_ResetBits(GPIOC, GPIO_Pin_4)

#define TURN_ON_ANL GPIO_ResetBits(GPIOB, GPIO_Pin_0)
#define TURN_OFF_ANL GPIO_SetBits(GPIOB, GPIO_Pin_0)

void SetControlRegister(void);
WORD NEXT_Convertion(WORD);
void StartConvertion(void);

/*****************************************************************************
** Defines and macros for AD7490 control register
*****************************************************************************/
#define WRITE bit(11)
#define SEQ bit(10)
#define SHADOW bit(3)
#define WEAK_TRI bit(2)
#define RANGE bit(1)
#define CODING bit(0)
#define NORMAL_MODE (bit(4) | bit(5))

#define bit(X) (WORD)(1 << X)
#define INPUT(X) ((X & 0x000F) << 6)
#define CONTROL_REGISTER(X) (((WORD)(WRITE | INPUT(X) | NORMAL_MODE | RANGE | CODING)) << 4)

/*******************************************************************************
* Function Name : Spi1Init
* Description : Configures the RTC.
* Input : Value of frequency prescalers divider
* Output : None
* Return : None
*******************************************************************************/
void Spi1Init() {
SPI_InitTypeDef SPI_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
/* Enable SPI1 and GPIO clocks */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);
/* Power on switch PB0 */
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOB, ENABLE); // !!! Вынести за пределы инициализации SPI1
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);
//TURN_ON_ANL;

/* Configure SPI1 pins: SCK, MISO and MOSI */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_6 | GPIO_Pin_7;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* Configure I/O for AD7490 software chip select */
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOC, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz;
GPIO_Init(GPIOC, &GPIO_InitStructure);
CS_DEASSERT;
/* SPI1 configuration */
SPI_DeInit(SPI1);
SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
SPI_InitStructure.SPI_DataSize = SPI_DataSize_16b;
SPI_InitStructure.SPI_CPOL = SPI_CPOL_High;
SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge;
SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_128;
SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
SPI_Init(SPI1, &SPI_InitStructure);

GPIO_PinAFConfig(GPIOA, GPIO_PinSource5, GPIO_AF_SPI1);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource6, GPIO_AF_SPI1);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource7, GPIO_AF_SPI1);
SPI_Cmd(SPI1, ENABLE); /* Enable SPI1 */

TURN_OFF_ANL; //Turn off adc
delay_ms(3000);

}


void SetControlRegister () {
BYTE i;
TURN_ON_ANL; // Turn on adc

for (i = 0; i < 2; i ++) {
CS_ASSERT;
NEXT_Convertion(0xFFFF); // First two cikles after supply on, DIN line is HIGH
CS_DEASSERT;
__nop(); __nop(); // Minimum delay t_quiet (accordingly datasheet ad7490)
}
CS_ASSERT;
NEXT_Convertion(CONTROL_REGISTER(0)); // Set "0" channel in control register
CS_DEASSERT;
__nop(); __nop(); // Minimum delay t_quiet (accordingly datasheet ad7490)
}

void StartConvertion () {
WORD result[16];
BYTE channel, a;
WORD settings;

for (channel = 0; channel < 15; channel ++) {
CS_ASSERT;
settings = CONTROL_REGISTER(channel+1);
result[channel] = NEXT_Convertion(settings); //Receiving prior convertion result and transmiting follow channel
CS_DEASSERT;
__nop(); __nop(); // Minimum delay t_quiet (accordingly datasheet ad7490)
}

CS_ASSERT;
settings = CONTROL_REGISTER(0); // Receiving last 15-th channel convertion result and set "0" channel in control register for next cikle
result[15] = NEXT_Convertion(settings);
CS_DEASSERT;
__nop(); __nop(); // Minimum delay t_quiet (accordingly datasheet ad7490)

printf ("convertion result: "); // Out result to console
for (channel = 0; channel < 16; channel ++) {
printf("0x%X ", result[channel]);
}


}
/*******************************************************************************
* Function Name : SPI_transmit
* Description : Sends a byte through the SPI interface and return the byte
* received from the SPI bus.
* Input : byte : byte to send.
* Output : None
* Return : The value of the received byte.
*******************************************************************************/
WORD NEXT_Convertion(WORD data) {
/* Loop while DR register in not emplty */
while (SPI_GetFlagStatus(SPI1, SPI_FLAG_TXE) == RESET);
/* Send byte through the SPI1 peripheral */
SPI1->DR = data;
/* Wait to receive a data */
while (SPI_GetFlagStatus(SPI1, SPI_FLAG_RXNE) == RESET);
/* Return the byte read from the SPI bus */
return SPI1->DR;
}
/******************************************************************************/

#define WRITE bit(11)
#define SEQ bit(10)
#define SHADOW bit(3)
#define WEAK_TRI bit(2)
#define RANGE bit(1)
#define CODING bit(0)