Download Issue 7 February 1980

SI.IPER DIIPER 3.WAY NEIJlORY DIAGI{OS?IC
by Tom Swan
ff
are experlencing unusual difficulties getting your
to rrmr you may have a bad nlemorjt chip. fhough your
VIF manr-ral coirtalns a simpl-e memory test, it is not desigrr:d i.r
cat':h what could be subtLe defecte in RAS. Plus, it is difficult
ta tesi.qil of meilory as tirat prograft was written to do ori1.y
yc,u
programs
ri:iia1J.
a:
sr':tion at a time.
This l-wa)' memory d.lagnostic wi.'Li. put your. VIP tirrougtr tlie 1.,61C B
using bl'te manipuLations that duplicate nost any conditiorr tu\hr
is Likely to experience during nornal pro€fram runs -- trrd th,,iln
ssne.
Even
pattern sensj.tivities are unlikely to
escape
Ei',p11tiny. Should your VIP pass thj.s test, you can be slre
riemory is as grrod as Dumbots, ff n,rt, yorlrll know er.actly
'the error oncrrrred,
,-
HCI'T
TO
you?'
wlrePt;
OPERATE
I,or,,l tire foLl.owing rnacliine larrguage p;'sgran lrtartlng a"t 0000,
then save one page (alscr at 0000) on ta,pe for frrture us€sr
Flip to t'un and the test will begin. . ALL avallable or-r]trd
ii,t$l except for 0000-00FF will. be-tested, if you snspect an
error in tlre first 2J6 bytes of RAIJi, you should switbh that
*hip firrt with a knovrn good one, therl run the test,
Thers are three parts to the test and €&,?h Fa6e i:lr tlispiayetl
on screen while it is being testedr
1
)
TESf A
i s f illed wi tli hytes
'F Full Pager Each pag* of RAlilp&ge
is checked for
from 00 to FF then the ful1
aceuracv.
?)
TEST B
,r- Byte by By'be r
from 00-FF
Each by'"be
and each
is filled with
value is checked fcr
val"ues
acerJr&cyr
-- Sequeneerr An entlre page is filled with a
sequence from 00-FF. the sequence is swapped
front to back twice then checked. for aceuracle
fhe test advanees through each page and will end autonnatieally
when the last page has been tested. Thls will hold true for
2K, 3K or 4K systerns. At the end of the testr provlrled there
were nc, errorsr all rnemory from 0100-0XFF (OX=highest on-card
RAI.I page ) i.s cLeared to 00 Wtes and an automatj.c return to the
VIP operating syptern ls performed so you do not have to reset
the eompr-tter to continue programning"
3)
IEST C
2 . O? .21+
*i,