w681308 Winbond Electronics Corp America, w681308 Datasheet - Page 48

• Manufacturer Part Number: w681308
• Description: Usb Audio Controller
• Manufacturer: Winbond Electronics Corp America

After finished shift out the command bytes, the FSM will change to DATA state if the Data_enb ( 0x14A1[4]) is true, or run
back to IDLE state if the Data_enb is fa
When FSM goes into Da
false, or shift in read data from external SPI device if SPI_RD (0x14A1[3]) is true. In bidirection mode, the control logic will
ignore SPI_RD (0x14A1[3]) and start to shift in/out the read/write data from/to external SPI device. After finishing shift out/in
the data bytes, the FSM will go back to IDLE state and wait for next transition.
14.4
The SPI module takes up to 5 bytes Register to write the control command and takes the 256x8 bytes RAM to do the
Read/Write access FIFO. In Bidirectional mode, the 256x8 bytes RAM will separate into two 28x8 bytes sections. One
(ADDR: 0x00~7F) for keep the transmit data, and the other one (ADDR: 0x80~0xFF) for store the receive data. Once the
Bidirectional mode is enabled, the SPI module
as in the unidirectional mode. It supports two memory access methods:
MCU always read/write the same register (0
read/write pointer automatically after each read/write. The current write and read pointer can be read at register 0x14AE and
0x14AF.
M
14.5
The SPI module supports two types of interrupt sources:
W
When TX/RX byte coun
For any other options, refer to the description of the specific registers in W681308 Design Guide.
CU can read/write any byte of the memory after
hen TX/RX byte counts (0x14AD) = DATA_LEN.
Data
FIFO like method
Direct access method
TX/RX finish interrupt
Middle flag interrupt
FIFO and RAM of SPI
Interrupt Sources
ts (0x14AD) = 16 * INTR_CNT (0x14A3[7:4]).
ta state, the control logic start to shift out write data to external SPI device if SPI_RD (0x14A1[3]) is
lse.
x14AC) with hardware control the memory read/write address, and increase the
will automatic put receive data
setting the read (0x14AF)/write (0x14AE) pointer first.
DATA
XXXX PRODUCT DESCRIPTION
48
IDLE
CMD
from ADDR: 0x80 instead of the ADDR: 0x00
1
W681308
Rev1.2