ADLINK Technology LEC-BT, Техническое описание

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12 Interfaces
3.9 I2C Bus
The LEC-BT provides four interfaces through the I2C bus for General Purpose, Power Manage-
ment, Camera, and LCD video I2C signals with operating speeds up to 400kHz. All I2C inter-
faces have 1.8V pull ups with 2.2k resistors.
3.10 SPI
The LEC-BT implements the SPI1 controller from the SoC (the SPI0 controller is not con-
nected). The SPI1 controller connects to the SMARC connector at pins P54, P56, P57, and P58
(pin P55 is not connected), which support two SPI Flash devices on the module for BIOS stor-
age. Consequently, the SPI0 pins P43, P44, P45, P46 on the SMARC connector are not con-
nected.
3.11 Serial (UART)
The LEC-BT provides three serial interfaces: Two ports are high-speed, 4-wire ports (with TX/
RX and RTS#/CTS#), and one port is 2-wire (with TX/RX only.)
3.12 I2S (Audio)
The LEC-BT supports an I2S audio interface as an alternate configuration to the default HD
Audio interface. The I2S signals are supported through the I2S0 pins on the SMARC connector,
and a programmable voltage regulator is used to switch between the I2S (1V8) and HDA (1V5).
The default is HDA, and the change to I2S mode is be made through the LPE Audio BIOS set-
ting. The I2S1 pins are not connected.
3.13 SD/SDIO Interface
Four parallel data lines comprise the SD/SDIO interface, supporting SD Card sockets.
3.14 eMMC Interface
The LEC-BT provides one 8-bit eMMC interface port, brought out from the SoC through the
SDMMC pins on the SMARC connector. If the eMMC NAND chip on the module is being used,
the SDMMC pins will not be available for the baseboard.
Table 3-1: I2C Signal Map
SMARC Connector I2C Pins Map To:
S5 / S7 SOC: SIO_I2C1
S48 / S49 BMC: I2C_GP
P105 / P106 SoC: DDI1_DDC (HDMI)
P121 / P122 SoC: SMB (DATA / CLK)
S139 / S140 BMC or RTD2136 LVDS_DID