Intel® Quartus® Prime Pro Edition User Guide: Platform Designer

ID 683609
Date 10/04/2021
Public

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5.1.8.1. Memory-Mapped Width Adapter

The Memory-Mapped Width Adapter is used in the Avalon® streaming domain and operates with information contained in the packet format.

The memory-mapped width adapter accepts packets on its sink interface with one data width and produces output packets on its source interface with a different data width. The ratio of the narrow data width must be a power of two, such as 1:4, 1:8, and 1:16. The ratio of the wider data width to the narrower width must also be a power of two, such as 4:1, 8:1, and 16:1 These output packets may have a different size if the input size exceeds the output data bus width, or if data packing is enabled.

When the width adapter converts from narrow data to wide data, each input beat's data and byte enables are copied to the appropriate segment of the wider output data and byte enables signals.

Figure 165. Width Adapter Timing for a 4:1 AdapterThis adapter assumes that the field ordering of the input and output packets is the same, with the only difference being the width of the data and accompanying byte enable fields. When the width adapter converts from wide data to narrow data, the narrower data is transmitted over several beats. The first output beat contains the lowest addressed segment of the input data and byte enables.