AT91SAM9G45-EKES Atmel, AT91SAM9G45-EKES Datasheet - Page 210

• Manufacturer Part Number: AT91SAM9G45-EKES
• Description: KIT EVAL FOR AT91SAM9G45
• Manufacturer: Atmel
• Series: AT91SAM Smart ARMr
• Type: MCUr

Specifications of AT91SAM9G45-EKES

• Contents: Board
• Processor To Be Evaluated: SAM9G45
• Data Bus Width: 32 bit
• Interface Type: I2C, SPI, UART
• Maximum Operating Temperature: + 50 C
• Minimum Operating Temperature: - 10 C
• Operating Supply Voltage: 1.8 V to 3.3 V
• For Use With/related Products: AT91SAM9G45
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: Q4626953

21.11.2
Figure 21-26. Write Access with NWAIT Assertion in Frozen Mode (EXNW_MODE = 10)
210
internally synchronized
NBS0, NBS1,
NBS2, NBS3,
A0,A1
NWAIT signal
AT91SAM9G45
Frozen Mode
D[31:0]
NWAIT
A
NWE
[25:2]
MCK
NCS
6
When the external device asserts the NWAIT signal (active low), and after internal synchroniza-
tion of this signal, the SMC state is frozen, i.e., SMC internal counters are frozen, and all control
signals remain unchanged. When the resynchronized NWAIT signal is deasserted, the SMC
completes the access, resuming the access from the point where it was stopped. See
26. This mode must be selected when the external device uses the NWAIT signal to delay the
access and to freeze the SMC.
The assertion of the NWAIT signal outside the expected period is ignored as illustrated in
21-27.
4
5
4
3
3
2
1
2
Write cycle
EXNW_MODE = 10 (Frozen)
WRITE_MODE = 1 (NWE_controlled)
NWE_PULSE = 5
NCS_WR_PULSE = 7
1
2
FROZEN STATE
1
2
1
2
1
0
0
6438F–ATARM–21-Jun-10
Figure 21-
Figure