Visible to Intel only — GUID: iga1401398388841
Ixiasoft
Visible to Intel only — GUID: iga1401398388841
Ixiasoft
46.3.2. Operations
The Avalon® -ST Round Robin Scheduler only requests 1 beat of data from a channel at each transaction. To request 1 beat of data from channel n, the scheduler writes the value 1 to address (4 ×n). For example, if the scheduler is requesting data from channel 3, the scheduler writes 1 to address 0xC.
At every clock cycle, the Avalon® -ST Round Robin Scheduler requests data from the next channel. Therefore, if the Avalon® -ST Round Robin Scheduler starts requesting from channel 1, at the next clock cycle, it requests from channel 2. The Avalon® -ST Round Robin Scheduler does not request data from a particular channel if the almost-full status for the channel is asserted. In this case, one clock cycle is used without a request transaction.
The Avalon® -ST Round Robin Scheduler cannot determine if the requested component is able to service the request transaction. The component asserts waitrequest when it cannot accept new requests.
Signal | Direction | Description |
---|---|---|
Clock and Reset | ||
clk | In | Clock reference. |
reset_n | In | Asynchronous active low reset. |
Avalon® -MM Request Interface | ||
request_address (log 2 Max_Channels–1:0) | Out | The write address used to signal the channel the request is for. |
request_write | Out | Write enable signal. |
request_writedata | Out | The amount of data requested from the particular channel. This value is always fixed at 1. |
request_waitrequest | In | Wait request signal, used to pause the scheduler when the agent cannot accept a new request. |
Avalon® -ST Almost-Full Status Interface | ||
almost_full_valid | In | Indicates that almost_full_channel and almost_full_data are valid. |
almost_full_channel (Channel_Width–1:0) | In | Indicates the channel for the current status indication. |
almost_full_data (log 2 Max_Channels–1:0) | In | A 1-bit signal that is asserted high to indicate that the channel indicated by almost_full_channel is almost full. |