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6 timing, Comment t – FUJITSU MHV2120AT User Manual

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5.6 Timing

C141-E218

5-153

Table 5.29 Ultra DMA data burst timing requirements (2 of 2)

MODE 0

(in ns)

MODE 1

(in ns)

MODE 2

(in ns)

MODE 3

(in ns)

MODE 4

(in ns)

MODE 5

(in ns)

NAME

MIN MAX MIN MAX MIN MAX MIN MAX MIN MAX MIN MAX

COMMENT

t

LI

0 150 0 150 0 150 0 100 0 100 0 75

Limited

interlock

time

(*1)

t

MLI

20 20 20 20 20 20

Interlock

time

with

minimum

(*1)

T

UI

0 0 0 0 0 0

Unlimited

interlock

time

(*1)

t

AZ

10 10 10 10 10 10

Maximum

time

allowed

for

output

drivers to release (from asserted or
negated)

t

ZAH

20 20 20 20 20 20

Minimum

delay

time

required

for

output

t

ZAD

0 0 0 0 0 0

Drivers

to

assert

or

negate

(from

released)

t

ENV

20 70 20 70 20 70 20 55 20 55 20 50

Envelope

time

(from

DMACK-

to

STOP and HDMARDY- during
data in burst initiation and from
DMACK to STOP during data out
burst initiation)

t

RFS

75 70 60 60 60 50

Ready-to-final-STROBE

time

(no

STROBE edges shall be sent this
long after negation of DMARDY-)

t

RP

160 125 100 100 100 85 Ready-to-pause

time

(that

recipient shall wait to pause after
negating DMARDY-)

t

IORDYZ

20 20 20 20 20 20

Maximum

time

before

releasing

IORDY

t

ZIORDY

0 0 0 0 0 0

Minimum

time

before

driving

IORDY (*4)

t

ACK

20 20 20 20 20 20

Setup

and

hold

times

for

DMACK- (before assertion or
negation)

t

SS

50 50 50 50 50 50

Time

from

STROBE

edge

to

negation of DMARQ or assertion
of STOP (when sender terminates
a burst)

*1: Except for some instances of t

MLI

that apply to host signals only, the parameters t

UI,

t

MLI

and t

LI

indicate sender-to-recipient or recipient-

to-sender interlocks, i.e., one agent (either sender or recipient) is waiting for the other agent to respond with a signal before
proceeding. t

UI

is an unlimited interlock that has no maximum time value. t

MLI

is a limited time-out that has a defined minimum. t

LI

is a limited time-out that has a defined maximum.

*2: 80-conductor cabling shall be required in order to meet setup (t

DS

, t

CS

) and hold (t

DH

, t

CH

) times in modes greater than 2.

*3: Timing for t

DVS

, t

DVH

, t

CVS

and t

CVH

shall be met for lumped capacitive loads of 15 and 40 pf at the connector where all signals (Data and

STROBE) have the same capacitive load value. Due to reflections on the cable, the measurement of these timings is not valid in a
normally functioning system.

*4: For all modes the parameter t

ZIORDY

may be greater than t

ENV

due to the fact that the host has a pull up on IORDY- giving it a known

state when not actively driven.

*5: The parameters t

DS

, and t

DH

for mode 5 is defined for a recipient at the end of the cable only in a configuration with one device at the

end of the cable.

Note:

All timing measurement switching points (low to high and high to low) shall be taken at 1.5V.

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