Browse Prior Art Database

Early Hold that Allows Reads on Other Cards to Continue

IP.com Disclosure Number: IPCOM000037645D
Original Publication Date: 1989-May-01
Included in the Prior Art Database: 2005-Jan-29
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Hardell, WR, Jr: AUTHOR [+3]

Abstract

Disclosed is a means to prevent the CPU from sending too much data to the memory card (stops present writes or holds off future writes), but allows present and future reads to continue.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 1

Early Hold that Allows Reads on Other Cards to Continue

Disclosed is a means to prevent the CPU from sending too much data to the memory card (stops present writes or holds off future writes), but allows present and future reads to continue.

This scheme is for a system that the CPU can send data to a memory card faster than the memory card can write the data into the DRAMs. The memory cards must have buffers for write data.

In this method for data HOLD the memory card must be able to predict when its buffers will fill up with data. The HOLD is activated before the data transfers must stop. This allows time for the pipe-line stages to empty. After the HOLD is released, the memory card may receive data again.

If the pending write is NOT complete after the pipe-line is empty; then the write will continue when HOLD is released. If the pending write is complete after the pipe-line is empty and a read is next; then the read may start immediately. If the pending write is complete after the pipe-line is empty and a write is next; then the next write will start when HOLD is released.

Disclosed anonymously.

1