The SPI Read operation for TXE81XX-Q1 is used to retrieve data from a specific register.
This operation involves sending a command to the
TXE81XX-Q1 to access a register and read its data.
SPI Read Operation Steps:
- Drive CS low. This enables
the internal shift register.
- Shift 24 bits of data into the device in a MSB first fashion. Data must be stable during the rising edge of SCLK
- The MSB bit must be a '1' indicating it is a read only transfer.
- The third data byte is NOP (no operation) which is dummy data byte.
- 16 bits of status is sent out on SDO. The first 2
bits are 2’b11 (indicating it to be a status segment). The next 6 bits are the bit 5 to 0
of Fault status register. The last 8 bits are all 0s.
- The read data is shifted out on SDO following the status bits.
- After the last bit of data is transferred, drive SCLK low if there is no more data to be transferred.
- De-assert CS (drive it
high) to end the read cycle.