Spectravideo MKI, Сервисное – Техническое руководство

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SA200
DISK
DRIVE
FUNCTIONAL OPERATIONS
The fo l l owing paragraphs def ine the func t i ona l as we l l as the t iming re l a t ion­
s h i p s of t he ope rat ions for the SA200 .
Power
App ly ing de powe r to the SA200 can be done in any se quenc.e . Howeve r , du r ing
pow e r- up , t he WR ITE GATE l i ne mu s t be he l d in a c t ive or at a h i gh l eve l . Th i s
w i l l p revent po s s i b l e "g l i t c h ing" o f the me dia . Af ter app l i ca t i on o f d e powe r ,
a 3 50 ms de lay shou ld be int roduced be fore any ope r a t i on i s per forme d . Af ter
powe r ing on , in i t i a l po s i t ion of the rea d /w r i t e hea d w i th re spec t to the data
t r ack s on t he me dia can be read in t he header I D f i e l d . I n order t o a s sure
prope r po s i t i oning of the read/wr i t e he a d a f te r powe r i ng on , a step out
ope r a t i on shou ld be per forme d unt i l t he TRACK 00 l i ne become s act i ve
( reca l i b r a te ) .
D r i ve S e l ec t i on
Drive se l ec t i on occurs whe n the app ro p r i a t e DRIVE SELECT l i ne i s ac t ivated and
t he p roper se l e c t j umpe r b l ock is insta l l e d .
Mot or On
In or der for the ho s t s y s t em to read or wri t e data , the de dr ive motor mus t be
t u rne d on . Th i s i s ac comp l i she d by a c t iva t ing t he M
O
T
O
R
ON
l ine . A
3 50
ms
de l a y mus t be i n t ro duce d a f t e r ac t iva t ing th i s l i ne to a l l ow the motor to come
up to speed be fore rea d ing or writ ing c an be accomp l i she d .
The mot o r mus t be t u rned o f f b y the ho s t system by deac t ivat i ng the
MOTOR ON
l i ne . T h i s shou ld be done i f the d r i ve ha not rece ived a new command w i th in 2
second s ( 1 0 re vo l u t i on s o f di ske t t e ) a f t e r comp l e t ing the execu t i o n of the las t
command .
This ensures max imum mot o r and me d i a l i f e _.
T r ack
S ee k ing the re a d /wr i t e he ad f rom one t rack to ano the r is accomp l i shed by :
( a ) WRITE GATE be ing inac t i ve .
( b )
Ac t i va t i ng the DRIVE SELECT l ine .
( c ) S e l e c t ing t he de s i re d d irect i on us ing the
DIRECTION SELECT
l ine .
( d ) Pul s i ng the STEP l i ne .
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