What does the double slash(transition 0 --> 1) mean in SRAM datasheet?

Question

The following image is from the datasheet of SRAM IS64WV51216BLL(page 15).

It is a SRAM's write timing diagram.I don't know the meaning of double transitions for WE signal.I have circled it in red.

SRAM write timing diagram

Timing Diagram Basics

Understanding Timing diagrams of digital systems

How to Read Timing Diagrams: A Maker’s Guide

Acturally I have searched many material,but nothing I wanted.Please help me!Thank you very much.

Answer 1

That is not multiple transitions, rather it is a timing window where the transition can happen which is bounded by two timing constraints: t_SA and t_PWE.

t_SA is the Address Setup time which is the earliest that W̄ can be asserted. t_PWE is the latest W̄ can be asserted and not violate the Pulse Width.