Datasheet

QuickLogic EOS S3 Ultra Low Power multicore MCU datasheet - Version 3.3d 27-129
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• Retrieving run-time data
Both of these operations are possible during either Smart Phone or Wearable EOS S3 modes. However, in a typical
Wearable application, there is no local Host to use the SPI Slave interface. Therefore, the following description is primarily
focused on the Smart Phone mode of operation.
During the EOS S3 platform non-debug setup operations, the Host system uses the SPI Slave module to write a
precompiled binary file to the EOS S3 device M4-F memory. In addition, the Host also writes precompiled binary files to
other memories such as those used by the FFE and the Sensor Manager. After completion, the Host system enables the
EOS S3 platform M4-F processor to execute the newly written binary code.
During normal the EOS S3 platform processing, the Host uses the SPI Slave interface to retrieve the results of the EOS S3
platform sensor fusion processing, and then it passes this data on to the corresponding application. Explanation regarding
how the Host knows when to retrieve results is beyond the scope of this section.
During the EOS S3 platform debugging operations, the Host uses the SPI Slave interface in ways that are similar to the
setup and normal processing operations addressed previously. Specifically, the Host uses the SPI Slave interface to
perform the following tasks:
• Load debug code
• Enable the M4-F to execute this code
• Retrieve the results
In addition, the Host can elect to only enable specific subsystems to diagnose. For example, the Host can configure the
FFE and Sensor Manager with diagnostic code, enable these subsystems to perform sensor fusion processing, and then
retrieve the result of this processing all without enabling the EOS S3 platform M4-F processor.
The following figure illustrates the SPI Slave interface.
Figure 14: SPI Slave Block Diagram
Programmable
Fabric
Host Application Processor (AP)
Interface
Top Level
Controller
(TLC)
Packet FIFO
DMA
Controller
AHB Bridge
SPI Interface
SPI Slave Module
Other EOS System Components
Example: M4 Memory, FFE, and SM Memories and Registers
SPI_SLAVE_MISO
SPI_SLAVE_CLK
SPI_SLAVE_SSN
SPI_SLAVE_MOSI
Sensor
Processing
Subsystems
EOS System
Example: M4 Processor
It is important to note that the SPI Slave module does not communicate directly to other functional blocks. Rather, it needs
to perform transfers through one or more AHB bridges for to access any register or memory within the EOS S3 platform.
For optimum performance of this interface during the Smart Phone mode, the EOS S3 platform needs to avoid using
common paths through the AHB infrastructure that are also used by the SPI Slave interface.