Integration Manual

TSD-19090601 - R15 Contents Page 47 of 143
1.9.3 SPI interfaces
1.9.3.1 SPI0 interface
The SPI0 1.8 V Serial Peripheral Interface supports communication with an external SPI slave devices, with
the module acting as SPI master, by means of the open CPU API, with the following pins:
 SPI_MOSI pin, SPI0 Master Output Slave Input (module output)
 SPI_MISO pin, SPI0 Master Input Slave Output (module input)
 SPI_SCLK pin, SPI0 Serial Clock (module output)
 SPI_CS pin, SPI0 Chip Select 0 (module output)
The SPI Serial Clock signal work on the frequency at 960KHz, 4.8MHz, 9.6MHz, 16MHz, 19.2MHz, 25MHz
and 50MHz, the default frequency is 50MHz.
The SPI0 interface can be configured as UART (UART4) interface by means of open CPU API or AT command
(see the TOBY-L3 series AT Commands Manual [2]), for communication with external devices with the
following configuration Table 13:
SPI Mode (SPI0)
4-wire UART Mode (UART4)
SPI_MOSI; SPI0 MOSI Pin (Module Output)
RXD4 (Module output); UART4 Receive Data
SPI_MISO; SPI0 MISO Pin (Module Input)
TXD4 (Module Input); UART4 Transmit Data
SPI_SCLK; SPI0 Clock Pin (Module Output)
CTS4 (Module Output); UART4 Clear To Send
SPI_CS; SPI0 Chip Select Pin (Module Output)
RTS4 (Module Input); UART4 Ready To Send
Table 14: TOBY-L3 series modules SPI0 PINs configuration
1.9.4 DDC (I2C) interfaces
1.9.4.1 I2C0 interface
The SDA and SCL pins represent the I2C0 1.8 V I
2
C bus compatible Display Data Channel (DDC) interface,
with the module acting as I
2
C master, available for
 communication with u-blox GNSS chips / modules
 communication with other external I
2
C devices by means of the open CPU API or AT commands
I2C0 interface pins of the module are open drain outputs conforming to the I
2
C bus specifications [7],
supporting up to 100 kbit/s data rate in Standard-mode, and up to 400 kbit/s data rate in Fast-mode.
Tashang has implemented special features to ease the design effort required for the integration of the
TOBY-L3 cellular module with a u-blox GNSS device.
Combining the TOBY-L3 cellular module with a u-blox GNSS device allows designers to have full access to
the positioning device directly via the cellular module: it relays control messages to the GNSS device via a