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Spc3 profibus interface center, 1 t + 74.2 – Siemens SPC3 User Manual

Page 53

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SPC3

PROFIBUS Interface Center

SPC3 Hardware Description

V1.3

Page 51

Copyright (C) Siemens AG 2003 All rights reserved.

2003/04

The request for a read access to SPC3 is derived from the positive edge of the E clock (in addition: XCS =
0, R W = 1). The request for a write access is derived from the negative edge of the E clock (in addition:
XCS = 0, R W = 0).

AMI-Vers.

ST-Vers.

No.

Parameter

Min

Max

Min

Max

Unit

40

E_Clock-Pulse-Width

8.5.4.1.1.1
T

+

74.2

3T + 74.2

ns

41

Address (AB

10..0

) Setuptime to E_Clock

10

10

ns

42

Address (AB

10..0

) Holdtime after E_Clock

5

5

ns

43

E_Clock

to Data Active Delay

5.7

17

5

ns

44

E_Clock

to Data valid (Zugriff auf RAM)

4T + 5

(88,3)

3T + 44.2

(107)

ns

E_Clock

to Data valid (Zugriff auf die Register)

4T + 18

(101,3)

4T + 21.9

(105,2)

ns

45

Data Holdtime after E_Clock

2

6.3

4

12

ns

46

R_W Setuptime to E_Clock

10

10

ns

47

R_W Holdtime after E_Clock

5

5

ns

48

XCS Setuptime to E_Clock

0

0

ns

49

XCS Holdtime after E_Clock

0

0

ns

50

Data Setuptime to E_Clock

10

10

ns

51

Data Holdtime after E_Clock

10

10

ns


Explanations:

T

=

Clock pulse cycle (48MHz)

TBD

=

to be defined

(1

=

Access to the RAM

(2

=

Access to the registers/latches

(3

=

For T = 48 MHz

Synchronous Motorola-Mode, Processor-Read-Timing

R_W

VALID

Data Valid

AB(10..0)

DB(7..0)

XCS

AS = log.'1'

E_Clock

41

Data Invalid

40

44

43

46

48

49

47

45

42