ADM-XRC SDK 2.8.1 User Guide (Linux)
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PLXSIM VHDL reference - locbus_agent_ddma

Declaration

Synopsis

Description

Declaration
component locbus_agent_ddma
    generic(
        tco_p2p    : in    time := 5 ns);
    port(
        ldreq_l    : in    std_logic;
        ldack_l    : out   std_logic;
        dd_in      : out   locbus_ddma_in_t;
        dd_out     : in    locbus_ddma_out_t);
end component;
Synopsis

Non-synthesizable testbench component that connects a stimulus process to a set of demand mode DMA pins on the FPGA (unit under test).

Description

This demand-mode DMA agent component can be instantiated in a testbench to provide demand-mode DMA stimulus to the FPGA. One instance of locbus_ddma_agent is normally required per demand-mode DMA channel used by the FPGA, and each instance is normally associated with a stimulus process. In the figure above, the signals on the right should be connected to the FPGA, while the signals on the left are driven by the stimulus process.

The generics should be mapped as follows:

Generic Map to...
tco_p2p A value of type time that represents the desired local bus clock-to-output delay for signals such as LDACK#). This parameter has a suitable default value so it need not be specified.

The first group of ports must be mapped to signals driven or used by the stimulus process associated with the local bus agent:

Port Map to...
dd_in A signal of type locbus_ddma_in_t, used by the stimulus process
dd_out A signal of type locbus_ddma_out_t, driven by the stimulus process

The second group of ports must be mapped to signals driven or input by the local bus arbiter:

Port Map to...
ldack_l A signal in the testbench that is input by the FPGA, corresponding to LDACK#
ldreq_l A signal in the testbench that is driven by the FPGA, corresponding to LDREQ#

 


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