The group you are posting to is a Usenet group. Messages posted to this group will make your email address visible to anyone on the Internet.
Your reply message has not been sent.
Your post was successful
 |
Newsgroups: alt.folklore.computers, comp.sys.dec
From: se...@fid.morgan.com (Seth Breidbart)
Date: 24 Sep 91 19:56:44 GMT
Local: Tues, Sep 24 1991 3:56 pm
Subject: Re: why three syncs?
:
>Any body know the reason for zeroing registers twice? I've seen it in the According to my memory, there was some computer that had two copies of >few pieces of BAL I've ever tried to understand.... each register in hardware. SUB R1,R1 would subtract one copy from the other. All instructions that stored into a register would store into both copies. However, when the machine was powered up, there could be garbage in the registers, and different garbage in the two copies. The first zeroing only ensured that the same garbage was in both copies. The second zeroing actually zeroed the register. Seth se...@fid.morgan.com You must Sign in before you can post messages.
To post a message you must first join this group.
Please update your nickname on the subscription settings page before posting.
You do not have the permission required to post.
| |||||||||||||