30.11MICROWIRE/SPI TIMING

 

 

 

 

Table 88

Microwire/SPI Signals

 

 

 

 

 

 

 

 

 

 

 

 

Symbol

Figure

 

 

Description

 

 

 

Reference

Min (ns)

Max (ns)

 

 

 

 

 

 

 

 

 

 

 

 

Microwire/SPI Input Signals

 

 

 

 

 

 

 

 

 

 

tMSKh

120

 

Microwire Clock High

 

At 2.0V (both edges)

80

-

tMSKl

120

 

Microwire Clock Low

 

At 0.8V (both edges)

80

-

 

120

 

 

 

 

SCIDL bit = 0; Rising Edge

 

-

 

 

 

 

 

(RE) MSK to next RE MSK

 

tMSKp

 

 

Microwire Clock Period

 

200

 

 

 

 

 

 

 

 

 

 

 

 

 

 

121

 

 

SCIDL bit = 1; Falling Edge

-

 

 

 

 

 

 

 

 

 

 

 

(FE) MSK to next FE MSK

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

tMSKh

120

MSK Hold (slave only)

 

After

 

 

 

 

goes inactive

40

-

 

MWCS

tMSKs

120

 

MSK Setup (slave only)

 

Before

 

 

 

 

goes active

80

-

 

MWCS

 

120

 

 

 

 

SCIDL bit = 0: After FE

 

-

 

 

 

 

 

MSK

 

 

 

 

 

 

 

 

 

tMWCSh

 

 

MWCS Hold (slave only)

 

40

 

 

 

 

 

 

 

 

 

 

 

 

 

 

121

 

 

SCIDL bit = 1: After RE

-

 

 

 

 

 

 

 

 

 

 

 

MSK

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

120

 

 

 

 

SCIDL bit = 0: Before RE

 

-

 

 

 

 

 

MSK

 

tMWCSs

 

 

 

 

 

 

 

 

 

MWCS Setup (slave only)

 

80

 

 

 

 

 

 

 

 

 

 

 

 

 

 

121

 

 

SCIDL bit = 1: Before FE

-

 

 

 

 

 

 

 

 

 

 

 

MSK

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

120

 

 

 

 

Normal Mode: After RE

 

-

 

 

 

 

 

MSK

 

 

 

 

Microwire Data In Hold (master)

 

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

122

 

 

Alternate Mode: After FE

-

 

 

 

 

 

 

 

 

 

 

 

MSK

 

tMDIh

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

120

 

 

 

 

Normal Mode: After RE

 

-

 

 

 

 

 

 

 

 

 

 

 

MSK

 

 

 

 

Microwire Data In Hold (slave)

 

40

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

122

 

 

Alternate Mode: After FE

-

 

 

 

 

 

 

 

 

 

 

 

MSK

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

120

 

 

 

 

Normal Mode: Before RE

 

-

 

 

 

 

 

MSK

 

tMDIs

 

 

Microwire Data In Setup

 

80

 

 

 

 

 

 

 

 

 

 

 

 

 

 

122

 

 

Alternate Mode: Before FE

-

 

 

 

 

 

 

 

 

 

 

 

MSK

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Microwire/SPI Output Signals

 

 

 

 

 

 

 

 

 

 

tMSKh

120

 

Microwire Clock High

 

At 2.0V (both edges)

40

-

tMSKl

120

 

Microwire Clock Low

 

At 0.8V (both edges)

40

-

 

120

 

 

 

 

SCIDL bit = 0: Rising Edge

 

-

 

 

 

 

 

(RE) MSK to next RE MSK

 

tMSKp

 

 

Microwire Clock Period

 

100

 

 

 

 

 

 

 

 

 

 

 

 

 

 

121

 

 

SCIDL bit = 1: Falling Edge

-

 

 

 

 

 

 

 

 

 

 

 

(FE) MSK to next FE MSK

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

tMSKd

120

 

MSK Leading Edge Delayed (master

Data Out Bit #7 Valid

0.5 tMSK

1.5 tMSK

 

only)

 

tMDOf

120

 

Microwire Data Float b

 

 

 

 

 

 

 

 

 

 

-

25

 

 

After RE on MWCS

 

(slave only)

 

 

120

 

 

 

 

Normal Mode: After FE

 

-

 

 

 

 

 

MSK

 

tMDOh

 

 

Microwire Data Out Hold

 

0.0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

121

 

 

Alternate Mode: After RE

 

 

 

 

 

 

 

 

 

 

 

 

 

MSK

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

tMDOnf

124

 

Microwire Data No Float (slave only)

 

After FE on

 

 

 

 

 

0

25

 

 

MWCS

CP3BT26

253

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Image 253
National CP3BT26 manual MICROWIRE/SPI Timing, Microwire/SPI Signals Symbol Description Reference Min ns