Specifications

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- DATA
TRACKS
40mm
DISK 10
TRt< 00
130 mm
DISK 00
HEAD SHIPPING ZONE
CYLINDER 353
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FIGURE 1·5. SHIPPING ZONE
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1.5.3 Track Acceaalng
Read/write head positioning is accomplished by:
a. Deactivating the WRITE GATE.
b. Activating the appropriate DRIVE SELECT line .
c. Being
in the READY condition with SEEK COMPlETE true.\
d. Selecttng the appropriate direction.
e. Pulsing the STEP
Un •.
f. Checking for the edge of the -SEEK COMPLETE line (changing from false to true).
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Stepping can occur at either the normal or buffered rate. DUring normal stepping,-the heads are repositioned at the
rate of incoming step pulses. In the case of buffered stepping, Incoming step pulses are received at a high rate and
are buffered Into counters. When all of the steps have been received, they are Issued to the stepper drivers at a
ramped stepping rate.
Each pulse will cause the heads to move either one track In or one track out, depending on the level of the DIREC-
TION IN line. A true on the DIRECTION IN line wUI cause an Inward seek: a false will result in an outward seek
toward track 00 .
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