National CP3BT26 Manuale Utente

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CP3
BT26
30.11
MICROWIRE/SPI TIMING
Table 88
Microwire/SPI Signals
Symbol Figure
Description
Reference
Min (ns)
Max (ns)
Microwire/SPI Input Signals
t
MSKh
Microwire Clock High
At 2.0V (both edges)
80
-
t
MSKl
Microwire Clock Low
At 0.8V (both edges)
80
-
t
MSKp
Microwire Clock Period 
SCIDL bit = 0; Rising Edge 
(RE) MSK to next RE MSK
200
-
SCIDL bit = 1; Falling Edge 
(FE) MSK to next FE MSK
-
t
MSKh
MSK Hold (slave only)
After MWCS goes inactive
40
-
t
MSKs
MSK Setup (slave only)
Before MWCS goes active
80
-
t
MWCSh
MWCS Hold (slave only)
SCIDL bit = 0: After FE 
MSK
40
-
SCIDL bit = 1: After RE 
MSK
-
t
MWCSs
MWCS Setup (slave only)
SCIDL bit = 0: Before RE 
MSK
80
-
SCIDL bit = 1: Before FE 
MSK
-
t
MDIh
Microwire Data In Hold (master)
Normal Mode: After RE 
MSK
0
-
Alternate Mode: After FE 
MSK
-
Microwire Data In Hold (slave)
Normal Mode: After RE 
MSK
40
-
Alternate Mode: After FE 
MSK
-
t
MDIs
Microwire Data In Setup
Normal Mode: Before RE 
MSK
80
-
Alternate Mode: Before FE 
MSK
-
Microwire/SPI Output Signals
t
MSKh
Microwire Clock High
At 2.0V (both edges)
40
-
t
MSKl
Microwire Clock Low
At 0.8V (both edges)
40
-
t
MSKp
Microwire Clock Period 
SCIDL bit = 0: Rising Edge 
(RE) MSK to next RE MSK
100
-
SCIDL bit = 1: Falling Edge 
(FE) MSK to next FE MSK
-
t
MSKd
MSK Leading Edge Delayed (master 
only)
Data Out Bit #7 Valid
0.5 t
MSK
1.5 t
MSK
t
MDOf
Microwire Data Float
 b
(slave only)
After RE on MWCS
-
25
t
MDOh
Microwire Data Out Hold
Normal Mode: After FE 
MSK
0.0
-
Alternate Mode: After RE 
MSK
t
MDOnf
Microwire Data No Float
 
(slave only)
After FE on MWCS
0
25