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SAM7S Series [DATASHEET]
6175M–ATARM–26-Oct-12
Table 20-5.
Read Handshake
Step
Programmer Action
Device Action
DATA I/O
1
Sets MODE and DATA signals
Waits for NCMD low
Input
2
Clears NCMD signal
Latch MODE and DATA
Input
3
Waits for RDY low
Clears RDY signal
Input
4
Sets DATA signal in tristate
Waits for NOE Low
Input
5
Clears NOE signal
Tristate
6
Waits for NVALID low
Sets DATA bus in output mode and outputs the
flash contents.
Output
7
Clears NVALID signal
Output
8
Reads value on DATA Bus
Waits for NOE high
Output
9
Sets NOE signal
Output
10
Waits for NVALID high
Sets DATA bus in input mode
X
11
Sets DATA in output mode
Sets NVALID signal
Input
12
Sets NCMD signal
Waits for NCMD high
Input
13
Waits for RDY high
Sets RDY signal
Input