Avalon® Interface Specifications

ID 683091
Date 9/26/2022
Document Table of Contents

A. Deprecated Signals

Deprecated signals implement functionality that is no longer required or has been superseded.


An output of Avalon® -MM hosts. Asserted for a single cycle at the beginning of a transfer. This signal is not used and is not necessary.

chipselect or chipselect_n

chipselect or chipselect_n: The chip select signal as described below was deprecated with the release of the Avalon® Tristate Conduit ( Avalon® -TC) interface type which includes a chip select signal.

Formerly chipselect was a 1-bit input to an Avalon® Memory-Mapped ( Avalon® -MM) agent interface signaling the beginning of a read or write transfer. The current Platform Designer interconnect filters read and write signals from hosts according to the address and address map. The Platform Designer interconnect only drives read and write signals to the appropriate Avalon® -MM agent, making a chip select unnecessary.

This signal dates from very early microprocessor designs. CPLDs decoded microprocessor addresses and generated chip selects for peripherals that were frequently asynchronous. With synchronous systems this signal is unnecessary.


Signal removed in version 1.2 of the Avalon® Interface Specifications. Formerly available to hosts to clear pending transfers for pipelined reads.