ST25R3916B datasheet(59/165 Pages) STMICROELECTRONICS

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DS13541 Rev 7

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ST25R3916B ST25R3917B

Application information

164

Loading data into FIFO or PT_Memory (FIFO/PT_Memory load)

Loading data into FIFO or PT_Memory is similar to writing data into addressable registers.

After the I2C slave address the mode byte to trigger a load of the FIFO or selected

PT_Memory area is sent (see Table 12) followed by the data bytes to be loaded.

Figure 25 shows how to load data into the FIFO.

Figure 25. FIFO load

Reading data from the FIFO

Reading data from the FIFO is similar to reading data from addressable registers. After the

I2C slave address the mode byte to trigger a read of the FIFO is sent. After receiving the

FIFO read mode byte the ST25R3916B and ST25R3917B send data bytes from the FIFO

for as long as the MCU keeps reading the bus.

Figure 26. FIFO read

Direct command mode

After the I2C slave address the mode byte to trigger a direct command is sent. As for SPI

some direct commands take some time to execute and no I2C access to the ST25R3916B

and ST25R3917B must be performed until the execution of the direct command is

completed. All such direct commands send an interrupt upon completion to notify the MCU

that the I2C bus can be used again.

MS51656V1

SCL

SDA

0 00 000

Data

Slave address

Data

FIFO load

MS51657V1

SCL

SDA

0 01

111

Slave address

FIFO read

Slave address

Data

ST25R3916B Datasheet(PDF) 59 Page - STMicroelectronics