Синхронный последовательный интерфейс: список регистров

  Unused

  QUAD_EN

Quad_Mode_EN
0: Quad mode disable
1: Quad mode enable
Cannot be written when XCH=1.
Note: Quad mode includes Quad-Input and Quad-Output.

  DRM

Master Dual Mode RX Enable
0: RX use single-bit mode
1: RX use dual mode
Cannot be written when XCH=1.
It is only valid when Quad_Mode_EN=0.

  DBC

Master Dummy Burst Counter
In master mode, this field specifies the burst number that should be sent
before receive in dual SPI mode. The data does not care by the device.
0: 0 burst
1: 1 burst
***
N: N bursts
Cannot be written when XCH=1.

  STC

Master Single Mode Transmit Counter
In master mode, this field specifies the burst number that should be sent in
single mode before automatically sending dummy burst. This is the first
transmit counter in all bursts.
0: 0 burst
1: 1 burst
***
N: N bursts
Cannot be written when XCH=1.

Команда U-Boot для чтения регистра

Bit fields structure

typedef union  spi_bcc
{
  struct
  {
   unsigned stc : 24;
   unsigned dbc : 4;
   unsigned drm : 1;
   unsigned quad_en : 1;
   unsigned unused0 : 2;
  } b;
   unsigned long w;
} SPI_BCC