公开(公告)号：US07594048B1

公开(公告)日：2009-09-22

申请号：US11893004

申请日：2007-08-14

Applicant: Gareth David Edwards ,  David Finlay Taylor ,  Duncan Andrew Cockburn ,  Douglas Michael Grant ,  Stuart Alan Nisbet

Inventor： Gareth David Edwards ,  David Finlay Taylor ,  Duncan Andrew Cockburn ,  Douglas Michael Grant ,  Stuart Alan Nisbet

IPC: G06F3/00

CPC classification number: G06F5/12

Abstract: Measuring transit time across an asynchronous first-in-first-out (FIFO) memory can include sampling an indication of a value of a read pointer of the FIFO memory at a sampling frequency that exceeds a frequency of a read clock and a write clock of the FIFO memory. An indication of a value of a write pointer of the FIFO memory can be sampled at the sampling frequency. For each sampling period, a measure of occupancy of the FIFO memory can be calculated according to a sampled pair including the indication of the value of the read pointer and the indication of the value of the write pointer. The measure of occupancy can be averaged over a predetermined number of cycles of the sampling frequency. The averaged measure of occupancy can be output as an indication of transit time across the FIFO memory.

Abstract translation: 跨越异步先入先出（FIFO）存储器测量传输时间可以包括以超过读取时钟的频率和读取时钟的采样频率对FIFO存储器的读指针的值的指示进行采样 FIFO存储器。 可以以采样频率对FIFO存储器的写指针的值的指示进行采样。 对于每个采样周期，可以根据包括读指针的值的指示和写指针的值的指示的采样对来计算FIFO存储器的占用量。 可以在采样频率的预定数量的周期内对占用的量度进行平均。 可以将占用的平均度量输出为FIFO存储器上的传输时间的指示。