Groups > comp.sys.apple2.programmer > #1374

Re: Can anyone see a way to improve this ?

Path	csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!eternal-september.org!feeder.eternal-september.org!mx02.eternal-september.org!.POSTED!not-for-mail
From	awanderin <awanderin@gmail.com>
Newsgroups	comp.sys.apple2.programmer
Subject	Re: Can anyone see a way to improve this ?
Date	Mon, 27 Oct 2014 21:35:29 -0600
Organization	A noiseless patient Spider
Lines	50
Message-ID	<m3oaswamta.fsf@gmail.com> (permalink)
References	<34030b70-c7cb-4b31-a99a-6b44c3877066@googlegroups.com>
Mime-Version	1.0
Content-Type	text/plain
Injection-Info	mx02.eternal-september.org; posting-host="adfb6bbd1e1493191f3136a944e5344e"; logging-data="13563"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19tP4bFP0KYq2IQkVaHJUeQadgDU2pVjsY="
User-Agent	Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux)
Cancel-Lock	sha1:zVVuqq1B81kbuq6SZDo+nPPCKNo= sha1:V7+El1FC8kGNHXPM6athHffdx6Y=
Xref	csiph.com comp.sys.apple2.programmer:1374

Show key headers only | View raw

mdj <mdj.mdj@gmail.com> writes:

> Hi,
>
> Below is a memory test loop for 1 page - assume the high order bytes
> get replaced for each page being tested. Zero page is deliberately
> avoided - this runs in either the language card or the $800-$BFFF area
> of main memory, testing pages of auxiliary memory without assuming any
> given byte of aux memory works.
>
> The obvious one is to unroll, which I'll do. Just wondering if I'm
> missing something else obvious.
>
> Thanks,
>
> Matt
>
>
>          LDX   #$00
> NEXTBYTE LDY   #$08
>          LDA   #$01
> NEXTBIT  EOR   #$FF       ; Set and check complement first
>          STA   $2000,X
>          CMP   $2000,X
>          BNE   ERROR
>          EOR   #$FF
>          STA   $2000,X
>          CMP   $2000,X
>          BEQ   CONT
> ERROR    JSR   FLAGERR
> CONT     ASL
>          DEY
>          BNE   NEXTBIT
>          INX
>          BNE   NEXTBYTE
>          RTS
> FLAGERR  RTS              ; Record this meaningfully in the future
>
>
>

For a thorough discussion of strong memory-checkers, see this article:

    http://www.ganssle.com/articles/ramtest.htm

I guess it depends on how confident you are in the machine's RAM in the
first place.

--
Jerry    awanderin at gmail dot com

Back to comp.sys.apple2.programmer | Previous | Next — Previous in thread | Find similar | Unroll thread

Thread

Can anyone see a way to improve this ? mdj <mdj.mdj@gmail.com> - 2014-10-27 05:04 -0700
  Re: Can anyone see a way to improve this ? "Anton Treuenfels" <teamtempest@yahoo.com> - 2014-10-27 08:38 -0500
  Re: Can anyone see a way to improve this ? Vladimir Ivanov <none@none.tld> - 2014-10-27 15:56 +0200
    Re: Can anyone see a way to improve this ? Michael J. Mahon <mjmahon@aol.com> - 2014-10-27 13:21 -0500
      Re: Can anyone see a way to improve this ? mdj <mdj.mdj@gmail.com> - 2014-10-27 17:48 -0700
        Re: Can anyone see a way to improve this ? Snertking <SNERTKING@GMAIL.COM> - 2014-10-27 21:28 -0400
          Re: Can anyone see a way to improve this ? mdj <mdj.mdj@gmail.com> - 2014-10-27 22:45 -0700
            Re: Can anyone see a way to improve this ? Michael J. Mahon <mjmahon@aol.com> - 2014-10-29 10:33 -0500
              Re: Can anyone see a way to improve this ? mdj <mdj.mdj@gmail.com> - 2014-10-29 22:54 -0700
                Re: Can anyone see a way to improve this ? qkumba <peter.ferrie@gmail.com> - 2014-10-31 14:46 -0700
      Re: Can anyone see a way to improve this ? Snertking <SNERTKING@GMAIL.COM> - 2014-10-27 21:25 -0400
      Re: Can anyone see a way to improve this ? michael.pohoreski@gmail.com - 2014-12-30 10:12 -0800
  Re: Can anyone see a way to improve this ? awanderin <awanderin@gmail.com> - 2014-10-27 21:35 -0600

csiph-web