AT45DB642D-CNU-SL954 ATMEL [ATMEL Corporation], AT45DB642D-CNU-SL954 Datasheet - Page 39

• Manufacturer Part Number: AT45DB642D-CNU-SL954
• Description: 64-megabit 2.7-volt Dual-interface DataFlash
• Manufacturer: ATMEL [ATMEL Corporation]

21.8
Figure 21-2. Rapid8 Mode
21.9
Note:
3542H–DFLASH–4/08
MOSI = Master Out, Slave In
MISO = Master In, Slave Out
The Master would be the ASIC/MCU and the Slave would be the memory device.
The Master always clocks data out on the rising edge of SCK and always clocks data in on the falling edge of SCK.
The Slave always clocks data out on the falling edge of SCK and always clocks data in on the rising edge of SCK.
Slave
Utilizing the Rapid8
Reset Timing
The CS signal should be in the high state before the RESET signal is deasserted.
A.
B.
C.
D.
E.
F.
G. Master clocks in BYTE h (last output byte).
SO or I/O7 - I/O0
SI or I/O7 - I/O0
I/O
SCK
Master clocks out BYTE 1 on the rising edge of SCK.
Slave clocks in BYTE 1 on the next rising edge of SCK.
Master clocks out BYTE 2 on the same rising edge of SCK.
Slave clocks in BYTE 6 (last input byte).
Slave clocks out BYTE a (first output byte).
Master clocks in BYTE a.
CS
7-0
(OUTPUT)
SCK/CLK
(INPUT)
RESET
CS
A
The Rapid8 functions like RapidS but with 8 bits of data instead of 1 bit. A full clock cycle must
be used to transmit data back and forth across the 8 bit bus. The DataFlash is designed to
always clock its data out on the falling edge of the SCK signal and clock data in on the rising
edge of SCK.
For full clock cycle operation to be achieved, when the DataFlash is clocking data out on the fall-
ing edge of SCK, the host controller should wait until the next falling edge of SCK to latch the
data in. Similarly, the host controller should clock its data out on the rising edge of SCK in order
to give the DataFlash a full clock cycle to latch the incoming data in on the next rising edge of
SCK.
1
B
BYTE 1
2
C
™
BYTE 2
HIGH IMPEDANCE
Function
3
BYTE 3
4
BYTE 4
t
V
5
BYTE 5
6
BYTE 6
D
7
E
BYTE a
8
F
BYTE b
9
BYTE c
10
BYTE d
11
BYTE e
t RST
12
t REC
BYTE f
13
HIGH IMPEDANCE
BYTE g
14
AT45DB642D
G
BYTE h
15
t CSS
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