Chapter 6 At Interface And Ata Commands; Introduction; Physical Interface; Signal Conventions - Samsung SPINPOINT V40 Series Product Manual

CHAPTER 6
6.1

Introduction

A Samsung disk drive with an Embedded AT Interface fully supports and enhances PC mass storage
requirements. The Samsung AT interface conforms to the ATA/ATAPI-6 standards in Cabling, in Physical
Signals, and in Logical Programming schemes. The Samsung Embedded AT controller joins the industry
premiere VLSI circuitry with ingenious programming skill that does not compromise performance or
reliability. Samsung integrates and delivers the cutting edge in technology. Samsung AT class disk drives are
designed to relieve and to enhance the I/O request processing function of system drivers.
6.2

Physical Interface

6.2.1 Signal Conventions

Signal names are shown in all upper case letters. Signals can be asserted (active, true) for either a high (more
positive voltage) or low (less positive voltage) state. A dash character (-) at the beginning or end of a signal
name indicates that it is asserted at the low level (active low). No dash or a plus character (+) at the beginning
or end of a signal name indicates it is asserted high (active high). An asserted signal may be driven high or
low by an active circuit, or it may be pulled to the correct state by the bias circuitry.
Control signals that are asserted for one function when high and asserted for another function when low are
named with the asserted high function name followed by a slash character (/). The asserted low function
name is followed with a dash (-) (e.g., BITENA/BITCLR- enables a bit when high and clears a bit when low).
All signals are TTL compatible unless otherwise noted. Negated means that the signal is driven by an active
circuit to the state opposite to the asserted state (inactive or false) or may be simply released (in which case
the bias circuitry pulls it inactive or false), at the option of the implementer.

6.2.2 Signal Summary

The physical interface consists of single-ended TTL compatible receivers and drivers communicating through
a 40/80-conductor flat ribbon non-shielded cable using an asynchronous interface protocol. The pin numbers
and signal names are shown in Table 6-1. Reserved signals are left unconnected.
SpinPoint V40 Product Manual
AT INTERFACE AND ATA COMMANDS
DISK DRIVE OPERATION
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