Visible to Intel only — GUID: vlv1678091535398
Ixiasoft
Visible to Intel only — GUID: vlv1678091535398
Ixiasoft
3.2.1. Asynchronous FIFO Parameterizable Macro Port Descriptions
Port | Type | Required | Description |
---|---|---|---|
wrclk | Input | Yes | Positive-edge-triggered clock. Use to synchronize the following ports:
|
rdclk | Input | Yes | Positive-edge-triggered clock. Use to synchronize the following ports:
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data | Input | Yes | Holds the data that is written in the FIFO when the wrreq signal is asserted. The port width is equal to the DATA_WIDTH parameter. |
wrreq | Input | Yes | Assert this signal to request for a write operation. Ensure that the following conditions are met:
|
rdreq | Input | Yes | Assert this signal to request for a read operation. The rdreq signal acts differently in normal mode and show-ahead mode. Ensure that the following conditions are met:
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aclr | Input | No | Assert this signal to clear all the output status ports, but the effect on the q output may vary for different FIFO configurations. |
q | Output | Yes | Shows the data read from the read request operation. The width of the q port must be equal to the width of the data port. The port width is equal to the DATA_WIDTH_A parameter. For the mixed width FIFO, the width of the q port can be different from the width of the data port. You need to ensure the width of the q port is equal to the DATA_WIDTH_B parameter. The FIFO macro supports a wide write port with a narrow read port, and vice versa. However, the width ratio is restricted by the type of RAM block, and in the power of 2. |
wrfull rdfull |
Output | No | When asserted, the FIFO is considered full. Do not perform write request operation when the FIFO is full. The rdfull signal functions as a combinational output instead of a derived version of the wrfull signal. Therefore, you must always refer to the wrfull port to ensure whether or not a valid write request operation can be performed, regardless of the target device. |
wrempty rdempty |
Output | No | When asserted, the FIFO is considered empty. Do not perform read request operation when the FIFO is empty. The wrempty signal functions as a combinational output instead of a derived version of the rdempty signal. Therefore, you must always refer to the rdempty port to ensure whether or not a valid read request operation can be performed, regardless of the target device. |
wrusedw rdusedw |
Output | No | Show the number of words stored in the FIFO. Ensure that the wrusedw port width is equal to the ADDR_WIDTH_A parameter, and the rdusedw port width is equal to the ADDR_WIDTH_B parameter. For the ASYNC_FIFO_MIXED_WIDTH function, the width of the wrusedw and rdusedw ports must be equal to the ADDR_WIDTH_A and ADDR_WIDTH_B parameters, respectively. The FIFO shows full even before the number of words stored reaches its maximum value. Therefore, you must always refer to the wrfull port for valid write request operation, and the rdempty port for valid read request operation regardless of the target device. |
byteena | Input | Yes | Byte enable port at Port A to masks the data_a port so that only specific bits of data are written to the memory. This port is enabled in FIFO because the pseudo RAM supports data with byte_size. |