Telit Wireless Solutions SE868SY-D, Hw Design Manual, Page: 20 / 44

SE868SY-D Hardware Design Guide
1VV0301705 Rev. 5 Page 20 of 44 2021-12-15
Not Subject to NDA
Table 13: UART Pins
•
HIF_SPI: slave SPI interface, speed up to 10Mbps.
Function Pin on SE868SY-D
HIF_SPI_SCLK 11
HIF_SPI_CS 23
HIF_SPI_MISO 24
HIF_SPI_MOSI 10
Table 14: SPI Pins
•
HIF_I2C: slave I
2
C interface, speed up to 400kbps in Fast mode and up to 3.4 Mbps
in High-Speed Mode.
Function Pin on SE868SY-D
HIF_I2C_SCL 11
HIF_I2C_SDA 10
Table 15: I2C Pins
5.2.2. Host Interface Selection
The different Host Interface (HIF) options described in the previous section can be
selected in the SE868SY-D via two pins, HIF_SEL_0 and HIF_SEL_1, whose values are
checked when the power is turned ON. HIF_SEL_0 and HIF_SEL_1 are internally pulled
down with a 47 k
Ω
resistor: this implies that the HIF is set to UART by default. SPI and
I2C can be selected by externally pulling up HIF_SEL_1 or HIF_SEL_0 to VDD, as shown
in Table 16. The recommended Pull Up values to select SPI or I2C is 4.7 k
Ω
.
HIF_SEL_1 HIF_SEL_0 Selected host interface
NC NC HIF_UART
NC PULL UP HIF_I2C
PULL UP NC HIF_SPI
Table 16: Settings for Host Interface Selection
Note: The configuration with both HIF_SEL_x pins pulled up is
reserved, and shall not be used.