All the ADI IP cores contains multiple AXI register map modules, which control a well specified part of the IP. To avoid complicated interconnections inside the IP, using the up_axi.v module, the AXI Memory Mapped interface is converted into a so called Microprocessor interface or uP interface. This interface has an independent write and read channel, and each channel contains an address bus, a data bus, a request (driven by master) and an acknowledge (driven by slave) control signals. All the uP interface signals names have a up_ prefix, this differentiate themselves clearly from other internal signals.
Interface | Pin | Type | Description |
---|---|---|---|
Clock and reset | |||
up_clk | input | Clock signal, should be connected to s_axi_aclk | |
up_rstn | input | An active low reset, should be connected to s_axi_aresetn | |
Read interface | |||
up_rreq | output | Read request from the processor | |
up_rack | input | Read acknowledge from the core | |
up_raddr | output[13:0] | Read address defined by the processor | |
up_rdata | input[31:0] | Read data, delivered by the core | |
Write interface | |||
up_wreq | output | Write request from the processor | |
up_wack | input | Write acknowledge from the core | |
up_waddr | output[13:0] | Write address defined by the processor | |
up_wdata | output[31:0] | Write data defined by the processor |
Note: The directions of the signals are defined from the masters (microprocessor) perspective.
The following timing diagram illustrates the signals and functionality of the interface. It show a register write access and two consecutive register read access.