DP8473 datasheet(2/28 Pages) NSC

2 / 28 page

General Description (Continued)

the data rate 83 ns125 ns208 ns 250 ns for data rates of

10M500k300k250 kbs respectively

Specifically to support the PC-AT and PC-XT design the

Floppy Disk Controller PLUS-2 includes address decode for

the A0 – A2 address lines the motordrive select register

data rate register for selecting 250300500 kbs Disk

Changed status dual speed spindle motor control low write

current and DMAinterrupt sharing logic The controller also

supports direct connection to the mP bus via internal 12 mA

buffers The controller also can be connected directly to the

disk drive via internal open drain high drive outputs and

Schmitt inputs

In addition to this logic the DP8473 includes many features

to ease design of higher performance drives and future con-

troller upgrades These include 10 Mbs data rate extend-

ed track range to 4096 Implied seeking working Scan Com-

mands motor control timing both standard IBM formats as

well as Sony 35

(ISO) formats and other enhancements

This device is available in a 52 pin Plastic Chip Carrier and

in a 48 pin Dual-In-Line package

Table of Contents

General Description

Pin Description

Functional Description

Result Phase Register Description

Processor Software Interface

Command Description Table

Command Descriptions

DC and AC Characteristics

Block Diagram

TLF9384 – 3

Note 1

The MTR2 MTR3 DR2 and DR3 are not available on the 48 pin DIP (DP8473N J) versions

Note 2

See

Figure 4 for filter description

Note 3

Total transistor count is 29700 (approx)

FIGURE 1 DP8473 Functional Block Diagram

DP8473 Datasheet(PDF) 2 Page - National Semiconductor (TI)