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Table 65, Table 66, Table 67 – Rainbow Electronics T89C51AC2 User Manual

Page 102

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102

T89C51AC2

Rev. B – 19-Dec-01

18.4.6 External Data Memory
Read Cycle

18.4.7 Serial Port Timing -
Shift Register Mode

Table 65. Symbol Description (F= 40 MHz)

Table 66. AC Parameters for a Fix Clock (F= 40 MHz)

Table 67. AC Parameters for a Variable Clock

ALE

PSEN

RD

PORT 0

PORT 2

A0-A7

DATA IN

ADDRESS

OR SFR-P2

T

AVWL

T

LLWL

T

RLAZ

ADDRESS A8-A15 OR SFR P2

T

RHDZ

T

WHLH

T

RLRH

T

LLDV

T

RHDX

T

LLAX

T

AVDV

Symbol

Parameter

T

XLXL

Serial port clock cycle time

T

QVHX

Output data set-up to clock rising edge

T

XHQX

Output data hold after clock rising edge

T

XHDX

Input data hold after clock rising edge

T

XHDV

Clock rising edge to input data valid

Symbol

Min

Max

Units

T

XLXL

300

ns

T

QVHX

200

ns

T

XHQX

30

ns

T

XHDX

0

ns

T

XHDV

117

ns

Symbol

Type

Standard

Clock

X2 Clock

X parameter
for -M range

Units

T

XLXL

Min

12 T

6 T

ns

T

QVHX

Min

10 T - x

5 T - x

50

ns

T

XHQX

Min

2 T - x

T - x

20

ns

T

XHDX

Min

x

x

0

ns

T

XHDV

Max

10 T - x

5 T- x

133

ns