User's Manual

FLC-BTM501 Datasheet
Flaircomm Microelectronics Confidential
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Figure 8: Example EEPROM Connection with I2C Interface
4.7.4 SPI
The synchronous serial port interface (SPI) can be used for system debugging. It can also be used for
in-system programming for the flash memory within the module. SPI interface uses the SPI_MOSI,
SPI_MISO, SPI_CSB and SPI_CLK pins. Testing points for the SPI interface are reserved on board
in case that the firmware shall be updated during manufacture.
The module operates as a slave and thus SPI_MISO is an output of the module. SPI_MISO is not in
high-impedance state when SPI_CSB is pulled high. Instead, the module outputs 0 if the processor is
running and 1 if it is stopped. Thus the module should NOT be connected in a multi-slave
arrangement by simple parallel connection of slave SPI_MISO lines.
Figure 9: Design SPI for In-System Programming and Debug