Visible to Intel only — GUID: iga1401317571160
Ixiasoft
Visible to Intel only — GUID: iga1401317571160
Ixiasoft
5.2. Functional Description
- Host Out Agent In (mosi)—Output data from the host to the inputs of the agents
- Host In Agent Out (miso)—Output data from a agent to the input of the host
- Serial Clock (sclk)—Clock driven by the host to agents, used to synchronize the data bits
- Agent Select (ss_n)— Select signal (active low) driven by the host to individual agents, used to select the target agent
The SPI core has the following user-visible features:
- A memory-mapped register space comprised of five registers: rxdata, txdata, status, control, and slaveselect
- Four SPI interface ports: sclk, ss_n, mosi, and miso
The registers provide an interface to the SPI core and are visible via the Avalon® memory-mapped interface agent port. The sclk, ss_n, mosi, and miso ports provide the hardware interface to other SPI devices. The behavior of sclk, ss_n, mosi, and miso depends on whether the SPI core is configured as a host or agent.
The SPI core logic is synchronous to the clock input provided by the Avalon® memory-mapped interface. When configured as a host, the core divides the Avalon® memory-mapped interface clock to generate the SCLK output. When configured as a agent, the core's receive logic is synchronized to SCLK input.
For more details, refer to the "Interval Timer Core" chapter.