uint8_t datablock_read(uint8_t* buff, uint32_t btr) {
  uint8_t token;

  uint32_t time = OSTime;

  while (1) {
    token = SPI_Read(0xFF);
    if (token != 0xFF)
      break;
    if ((OSTime - time) > 100)
      break;
  }

  if (token != 0xFE)
    return 0;

  #if USE_DMA        
    SPI_Read_PDC(buff, btr);
  #else
    do {
      SPI_Read(buff++);
    } while (btr -= 1);
  #endif
  SPI_Read(0xFF);
  SPI_Read(0xFF);

  return 1;
}

***** *

unsigned short SPI_Read(PSPI self, unsigned short data) {

  while ((BASE_SPI->SPI_SR &AT91C_SPI_TDRE) == 0)
;

  self->BASE_SPI->SPI_TDR = (data &0xFFFF);


  while (0 == (self->BASE_SPI->SPI_SR &AT91C_SPI_RDRF))
;

  return ((self->BASE_SPI->SPI_RDR) &0xFFFF);
}


short SPI_Read_PDC(PSPI self, void* data, unsigned short count) {

  self->BASE_SPI->SPI_RDR;
  self->BASE_SPI->SPI_SR;

  self->BASE_SPI_PDC->PDC_RPR = (unsigned int)data;
  self->BASE_SPI_PDC->PDC_RCR = count;

  self->BASE_SPI_PDC->PDC_PTCR = AT91C_PDC_RXTEN;
  self->BASE_SPI->SPI_IER = (AT91C_SPI_ENDRX);

  if (SPI_Send_PDC(self, dma_dummy, count) == count) {
    xSemaphoreTake(self->RXSemaphore, timeout);
  }

  self->BASE_SPI->SPI_IDR = AT91C_SPI_ENDRX;
  self->BASE_SPI_PDC->PDC_RCR = 0;

  (unsigned long)self->BASE_SPI->SPI_SR;
  (unsigned long)self->BASE_SPI->SPI_RDR;

  self->BASE_SPI_PDC->PDC_PTCR = AT91C_PDC_RXTDIS;

  unsigned short res = count - (self->BASE_SPI_PDC->PDC_RCR);

  return res;
}

  if (SPI_Send_PDC(self, dma_dummy, count) == count) {
    xSemaphoreTake(self->RXSemaphore, timeout);
  }

short SPI_Read_PDC(PSPI self, void* data, unsigned short count) {

    PSPI_BASE->SPI_RPR = (UINT)buff; // destination address
    PSPI_BASE->SPI_RCR = btr; // number of frames (here: frame=byte)
    // SPI PDC TX buffer (dummy bytes):
    PSPI_BASE->SPI_TPR = (UINT)dma_dummy; // source address
    PSPI_BASE->SPI_TCR = btr; // number of frames (here: frame=byte)
    
    PSPI_BASE->SPI_PTCR = AT91C_PDC_TXTEN | AT91C_PDC_RXTEN;
        
    while( !( (PSPI_BASE->SPI_SR) & AT91C_SPI_RXBUFF ) ) {
        // wait for RX Buffer Full (counters 0)
    }
}