DISK DRIVE OPERATION

6.7.4.2Ultra DMA data burst timing requirements

Table 6-19Ultra DMA data burst timing requirements

Name

Mode 0

Mode 1

Mode 2

Mode 3

Mode 4

Mode 5

Comment

 

 

(ns)

(ns)

(ns)

(ns)

(ns)

(ns)

(see Notes 1 and 2)

 

 

 

min

max

min

max

min

max

min

max

min

max

min

max

 

 

t2CYCTYP

240

 

160

 

120

 

90

 

60

 

40

 

Typical sustained average two cycle time

tCYC

112

 

73

 

54

 

39

 

25

 

16.8

 

Cycle time allowing for asymmetry and

 

 

 

 

 

 

 

 

 

 

 

 

 

closk variations (from STROBE edge to

 

 

 

 

 

 

 

 

 

 

 

 

 

STROBE edge)

 

 

t2CYC

230

 

154

 

115

 

86

 

57

 

38

 

Two cycle time allowing for clock

 

 

 

 

 

 

 

 

 

 

 

 

 

variations (from rising edge to next rising

 

 

 

 

 

 

 

 

 

 

 

 

 

edge or from falling edge to next falling

 

 

 

 

 

 

 

 

 

 

 

 

 

edge of STROBE)

 

 

tDS

15

 

10

 

7

 

7

 

5

 

4.0

 

Data setup time at recipient

 

 

tDH

5

 

5

 

5

 

5

 

5

 

4.6

 

Data hold time at recipient

 

 

tDVS

70

 

48

 

30

 

20

 

6

 

4.8

 

Data valid setup time at sender (from data

 

 

 

 

 

 

 

 

 

 

 

 

 

valid until STROBE edge) (see Note 4)

tDVH

6

 

6

 

6

 

6

 

6

 

4.8

 

Data valid hold time at sender (from

 

 

 

 

 

 

 

 

 

 

 

 

 

STROBE edge until data may become

 

 

 

 

 

 

 

 

 

 

 

 

 

invalid) (see Note 4)

 

 

tFS

0

230

0

200

0

170

0

130

0

120

 

90

First STROBE time (for device to

first

 

 

 

 

 

 

 

 

 

 

 

 

 

negate DSTROBE from STOP during a

 

 

 

 

 

 

 

 

 

 

 

 

 

data in burst)

 

 

tLI

0

150

0

150

0

150

0

100

0

100

0

75

Limited interlock time (see Note 3)

 

tMLI

20

 

20

 

20

 

20

 

20

 

20

 

Interlock time with minimum (see Note 3)

tUI

0

 

0

 

0

 

0

 

0

 

0

 

Unlimited interlock time (see Note 3)

 

tAZ

 

10

 

10

 

10

 

10

 

10

 

10

Maximum time allowed for output drivers

 

 

 

 

 

 

 

 

 

 

 

 

 

to release (from asserted or negated)

 

tZAH

20

 

20

 

20

 

20

 

20

 

20

 

Minimum delay time required for output

tZAD

0

 

0

 

0

 

0

 

0

 

 

 

Drivers to assert or negate (from released)

tENV

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

 

tSR

 

50

 

30

 

20

 

NA

 

NA

 

NA

STROBE-to-DMARDY-time

(if

 

 

 

 

 

 

 

 

 

 

 

 

 

DMARDY- is negated before this long

 

 

 

 

 

 

 

 

 

 

 

 

 

after STROBE edge, the recipient shall

 

 

 

 

 

 

 

 

 

 

 

 

 

receive no more than one additional data

 

 

 

 

 

 

 

 

 

 

 

 

 

word)

 

 

tRFS

 

75

 

70

 

60

 

60

 

60

 

50

Ready-to-final-STROBE

time

(no

 

 

 

 

 

 

 

 

 

 

 

 

 

STROBE edges shall be sent this long

 

 

 

 

 

 

 

 

 

 

 

 

 

after negation of DMARDY-)

 

tRP

160

 

125

 

100

 

100

 

100

 

 

85

Ready-to-pause time (that recipient shall

 

 

 

 

 

 

 

 

 

 

 

 

 

wait to pause after negating DMARDY-)

tIORDYZ

 

20

 

20

 

20

 

20

 

20

 

20

Maximum time before releasing IORDY

tZIORDY

0

 

0

 

0

 

0

 

0

 

0

 

Minimum time before driving STROBE

 

 

 

 

 

 

 

 

 

 

 

 

 

(see note 5)

 

 

tACK

20

 

20

 

20

 

20

 

20

 

20

 

Setup and hold times for DMACK-before

 

 

 

 

 

 

 

 

 

 

 

 

 

assertion or negation).

 

 

tSS

50

 

50

 

50

 

50

 

50

 

50

 

Time from STROBE edge to negation of

 

 

 

 

 

 

 

 

 

 

 

 

 

DMARQ or assertion of

STOP (when

 

 

 

 

 

 

 

 

 

 

 

 

 

sender terminates a burst)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SpinPoint V40 Product Manual

97

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Samsung 3.5 hard disk drives, spinpoint v40 manual 19Ultra DMA data burst timing requirements