SARA-R4 series - System integration manual
UBX-16029218 - R20 System description Page 38 of 128
C1-Public
The SARA-R4 series module itself acts as a USB device and can be connected to a USB host such as
a Personal Computer or an embedded application microprocessor equipped with compatible drivers.
The USB_D+/USB_D- lines carry USB serial bus data and signaling according to the Universal Serial
Bus revision 2.0 specification [6], while the VUSB_DET input pin senses the VBUS USB supply
presence (nominally 5 V at the source) to detect the host connection and enable the interface. Neither
the USB interface, nor the whole module is supplied by the VUSB_DET input, which senses the USB
supply voltage and absorbs few microamperes.
The USB interface of SARA-R410M and SARA-R412M modules is controlled and operated with:
• AT commands according to 3GPP TS 27.007 [8], 3GPP TS 27.005 [9]
• u-blox AT commands (see the SARA-R4 series AT commands manual [2])
SARA-R410M and SARA-R412M modules provide two USB functions:
• AT commands and data communication
• Diagnostic log
SARA-R422, SARA-R422S and SARA-R422M8S modules provide the following USB function:
• Diagnostic log
The USB profile of SARA-R4 series modules identifies itself by dedicated VID (Vendor ID) and PID
(Product ID) combination, included in the USB device descriptor following USB 2.0 specifications [6]:
• VID = 0x05C6
• PID = 0x90B2
1.9.3 SPI interface
☞ The SPI interface is not supported by current product versions: the SPI interface pins should not
be driven by any external device.
SARA-R410M and SARA-R412M modules include a Serial Peripheral Interface (I2S_WA / SPI_MOSI,
I2S_RXD / SPI_MISO, I2S_CLK / SPI_CLK, and I2S_TXD / SPI_CS) designed to communicate with
compatible external SPI devices.
1.9.4 SDIO interface
☞ The SDIO interface is not supported by current product versions: the SDIO interface pins should
not be driven by any external device.
The SARA-R410M and SARA-R412M modules include a 4-bit Secure Digital Input Output interface
(SDIO_D0, SDIO_D1, SDIO_D2, SDIO_D3, SDIO_CLK, and SDIO_CMD) designed to communicate with
compatible external SDIO devices.
1.9.5 DDC (I2C) interface
☞ The I2C interface is not supported by SARA-R410M-01B product version: the I2C interface pins
should not be driven by any external device.
SARA-R4 series modules include an I2C-bus compatible DDC interface (SDA, SCL lines) available to
communicate with an external u-blox GNSS receiver