Универсальный асинхронный приемо-передатчик: список регистров

  RESERV

Reserved

  AAD_ADDR_F

In AAD mode, when UART receives an address byte and the byte is the same
as RS485_ADDR_MATCH, this bit will be set to 1. If RS485 interrupt is
enabled, the RS485 interrupt will arrive.
Write 1 to clear this bit and reset the RS485 interrupt.

  RS485_ADDR_DET_F

This is a flag of the detected address bytes. When UART receives an address
byte, this bit will be set to 1. If the RS485 Interrupt is enabled, the RS485 interrupt will arrive.

1:An address byte is detected
0:No address byte is detected
Write 1 to clear this bit and reset the RS485 interrupt.

  Unused

  RX_BF_ADDR

In NMM mode, If setting this bit to 1, UART will receive all the bytes into
FIFO before receiving an address byte. If setting to 0, it will not.
1:Receive
0:Not Receive

  RX_AF_ADDR

In NMM mode, if setting this bit to 1, UART will receive all the bytes into
FIFO after receiving an address byte. If setting to 0, it will not.
1:Receive
0:Not Receive

  RS485_SLAVE_MODE_SEL

RS485 Slave Mode
00: Normal Multidrop Operation(NMM)
01: Auto Address Detection Operation(AAD)
10: Reserved
11: Reserved

Команда U-Boot для чтения регистра

Bit fields structure

typedef union  uart_485_ctl
{
  struct
  {
   unsigned rs485_slave_mode_sel : 2;
   unsigned rx_af_addr : 1;
   unsigned rx_bf_addr : 1;
   unsigned unused0 : 1;
   unsigned rs485_addr_det_f : 1;
   unsigned aad_addr_f : 1;
   unsigned reserv : 25;
  } b;
   unsigned long w;
} UART_485_CTL