Spectravideo MKI, Сервисное – Техническое руководство

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" S o f t E rror" De tecti on and Cor re c t ion
Sof t errors are usua l ly cause d by:
a. Airb orne contaminants tha t pass be tween the rea d/w r i te head and the d isk .
Usua l ly, these contaminan ts can be remove d by the ca r t r idge se l f- c lea n i ng
wipe r.
b. Random e lec t r i ca l no ise tha t usua l ly las ts for a few m icroseconds .
c. Sma l l de fects in t he w r i t ten da ta and / or track not de tected d u r ing t he
w rite opera t ion tha t ma y ca use a sof t error du ring a read .
d. W orn or de fec t i ve l oad pad .
e.
Improper g roundi ng of the powe r supp ly, dr ive, and / or hos t sys tem.
f. Im pr oper mot or s peed.
The fo l l owin g proce du res a re re commende d t o recover f rom the above men t ione d
s of t err ors:
a. ?e-read the t rack ten times or unt i l da ta is recove red .
b. If data is not recove red af te r per form ing s tep (a ), access head to
adjacent track in same d i rec tion previous ly moved, then re t u rn to
des ired track .
c. Repeat step ( a ).
d. If data is no t recove red, er ror is no t recovera b le .
Wri te E rror
If an error occurs d u ri ng a wri te opera t ion, i t w i l l be detected on the nex t
revo luti on b y doing a read opera t i on, commonly ca l led a "write check ." To
correct the er ror, anothe r w r i te and check operation mus t be done . I f the
wri te operat i on is not success f u l a f ter ten a t temp ts, a read ope ra t ion should
be a ttem pted on another t rack to determine w he the r the media or the dr ive is
fai
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in g. If the e r ror s t i
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pers ists, t he d isket te shou ld be rep lace d and the
ab ove pr ocedure repea ted . I f the fa i lure st i l l e x is ts, cons i der the dr ive
defecti ve. If t he fa i lure disappears, cons ider t he orig i na l d iske t te de fec t ive
and disca rd i t.
Read Error
Mos t errors tha t occur w i l l be "soft errors ." In these cases, pe rfo rmi ng an
error recover y proce du re w i l l recover the da ta.
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