Datasheet

ZED-F9T-Data sheet
5 Communications interfaces
There are several communications interfaces including UART, SPI, I2C
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and USB.
All the inputs have internal pull-up resistors in normal operation and can be left open if not used.
All the PIOs are supplied by VCC, therefore all the voltage levels of the PIO pins are related to VCC
supply voltage.
5.1 UART interface
The UART interfaces support configurable baud rates. See the ZED-F9T Integration manual [1].
Hardware flow control is not supported.
The UART1 is enabled if D_SEL pin of the module is left open or "high".
Symbol Parameter Min Max Unit
R
u
Baud rate 9600 921600 bit/s
Δ
Tx
Tx baudrate accuracy -1% +1% -
Δ
Rx
Rx baudrate tolerance -2.5% +2.5% -
Table 12: ZED-F9T UART specifications
5.2 SPI interface
The ZED-F9T has an SPI slave interface that can be selected by setting D_SEL = 0. The SPI slave
interface is shared with UART1 and I2C pins. The SPI pins available are:
• SPI_MISO (TXD)
• SPI_MOSI (RXD)
• SPI_CS_N
• SPI_CLK
The SPI interface is designed to allow communication to a host CPU. The interface can be operated
in slave mode only. Note that SPI is not available in the default configuration because its pins are
shared with the UART and I2C interfaces. The maximum transfer rate using SPI is 125 kB/s and the
maximum SPI clock frequency is 5.5 MHz.
This section provides SPI timing values for the ZED-F9T slave operation. The following tables
present timing values under different capacitive loading conditions. Default SPI configuration is
CPOL = 0 and CPHA = 0.
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I2C is a registered trademark of Philips/NXP
UBX-18053713 - R06
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5 Communications interfaces Page 14 of 23
C1-Public Early production information