SPI Engine Offload Module#

The SPI Engine Offload peripheral allows to store a SPI Engine command and SDO data stream in a RAM or ROM module. The command stream is executed when the trigger signal is asserted. This allows the execution of SPI transactions with a very short delay in reaction to a event.

Files#

Name	Description
library/spi_engine/spi_engine_offload/spi_engine_offload.v	Verilog source for the peripheral.
library/spi_engine/spi_engine_offload/spi_engine_offload_ip.tcl	TCL script to generate the Vivado IP-integrator project for the peripheral.

Configuration Parameters#

Name	Description	Default Value	Choices/Range
`ASYNC_SPI_CLK`	If set to 1 the `ctrl_clk` and `spi_clk` are assumed to be asynchronous.	`False`
`ASYNC_TRIG`	If set to 1, the trigger input is considered asynchronous to the module.	`False`
`CMD_MEM_ADDRESS_WIDTH`	Configures the size of the command stream storage. The size is `2**CMD_MEM_ADDR_WIDTH` entries.	`4`	From 1 to 16.
`SDO_MEM_ADDRESS_WIDTH`	Configures the size of the SDO data stream storage. The size is `2**SDO_MEM_ADDR_WIDTH` entries.	`4`	From 1 to 16.
`DATA_WIDTH`	Data width of the parallel data stream. Will define the transaction’s granularity. Supported values: 8/16/24/32	`8`	From 8 to 256.
`NUM_OF_SDI`	Number of multiple SDI lines, (min: 1, max: 8)	`1`	From 1 to 8.
`SDO_STREAMING`	Enables the s_axis_sdo interface. This allows for sourcing the SDO data stream from a DMA or other similar sources, useful for DACs.	`False`

Signal and Interface Pins#

spi_engine_ctrl

SPI Engine Control Interface controller. SPI Engine Control stream that contains commands and data.

Physical Port	Logical Port	Direction
`cmd_ready`	`cmd_ready`	in
`cmd_valid`	`cmd_valid`	out
`cmd`	`cmd_data`	out [15:0]
`sdo_data_ready`	`sdo_ready`	in
`sdo_data_valid`	`sdo_valid`	out
`sdo_data`	`sdo_data`	out [7:0]
`sdi_data_ready`	`sdi_ready`	out
`sdi_data_valid`	`sdi_valid`	in
`sdi_data`	`sdi_data`	in [7:0]
`sync_ready`	`sync_ready`	out
`sync_valid`	`sync_valid`	in
`sync_data`	`sync_data`	in [7:0]

spi_engine_offload_ctrl

SPI Engine Offload Control Interface subordinate. Control interface which allows to re-program the stored command and SDO data stream.

Physical Port	Logical Port	Direction
`ctrl_cmd_wr_en`	`cmd_wr_en`	in
`ctrl_cmd_wr_data`	`cmd_wr_data`	in [15:0]
`ctrl_sdo_wr_en`	`sdo_wr_en`	in
`ctrl_sdo_wr_data`	`sdo_wr_data`	in [7:0]
`ctrl_enable`	`enable`	in
`ctrl_enabled`	`enabled`	out
`ctrl_mem_reset`	`mem_reset`	in
`status_sync_ready`	`sync_ready`	in
`status_sync_valid`	`sync_valid`	out
`status_sync_data`	`sync_data`	out [7:0]

offload_sdi

Streaming AXI controller Output stream of the received SPI data.

Physical Port	Logical Port	Direction
`offload_sdi_valid`	`TVALID`	out
`offload_sdi_ready`	`TREADY`	in
`offload_sdi_data`	`TDATA`	out [7:0]

s_axis_sdo

Enabled if SDO_STREAMING = 1.

Streaming AXI peripheral Input stream for SPI data to be sent. Only present when SDO_STREAMING parameter is set to 1.

Physical Port	Logical Port	Direction	Dependency
`s_axis_sdo_ready`	`TREADY`	out	`SDO_STREAMING = 1`
`s_axis_sdo_valid`	`TVALID`	in	`SDO_STREAMING = 1`
`s_axis_sdo_data`	`TDATA`	in [7:0]	`SDO_STREAMING = 1`

Ports

Physical Port	Direction	Description
`ctrl_clk`	in	The `spi_engine_offload_ctrl` signals are synchronous to this clock. Bus `spi_engine_offload_ctrl` is synchronous to this clock domain.
`spi_clk`	in	The `spi_engine_ctrl` signals, `offload_sdi` signals and trigger are synchronous to this clock. Bus `spi_engine_ctrl_offload_sdi_s_axis_sdo` is synchronous to this clock domain.
`spi_resetn`	in	Synchronous active low reset - Resets the internal state machine of the core. Bus `spi_engine_ctrl_offload_sdi_s_axis_sdo` is synchronous to this reset signal.
`trigger`	in	When asserted the stored command and data stream is send out on the `spi_engine_ctrl` interface.