Atmel Evaluation Kit for AT32uC3A0512, 32-Bit AVR Microcontroller Atmel ATEVK1105 ATEVK1105 Fiche De Données
Codes de produits
ATEVK1105
430
AT32UC3A
28.8.5
SDRAMC Low Power Register
Register Name
:
LPR
Access Type
:
Read/Write
Reset Value
:
0x0
•
LPCB: Low-power Configuration Bits
•
PASR: Partial Array Self-refresh (only for low-power SDRAM)
PASR parameter is transmitted to the SDRAM during initialization to specify whether only one quarter, one half or all banks
of the SDRAM array are enabled. Disabled banks are not refreshed in self-refresh mode. This parameter must be set
according to the SDRAM device specification.
After initialization, as soon as PASR field is modified and self-refresh mode is activated, the Extended Mode Register is
After initialization, as soon as PASR field is modified and self-refresh mode is activated, the Extended Mode Register is
accessed automatically and PASR bits are updated before entry in self-refresh mode.
•
•
TCSR: Temperature Compensated Self-Refresh (only for low-power SDRAM)
TCSR parameter is transmitted to the SDRAM during initialization to set the refresh interval during self-refresh mode
depending on the temperature of the low-power SDRAM. This parameter must be set according to the SDRAM device
specification.
After initialization, as soon as TCSR field is modified and self-refresh mode is activated, the Extended Mode Register is
After initialization, as soon as TCSR field is modified and self-refresh mode is activated, the Extended Mode Register is
accessed automatically and TCSR bits are updated before entry in self-refresh mode.
•
•
DS: Drive Strength (only for low-power SDRAM)
DS parameter is transmitted to the SDRAM during initialization to select the SDRAM strength of data output. This parame-
ter must be set according to the SDRAM device specification.
31
30
29
28
27
26
25
24
–
–
–
–
–
–
–
–
23
22
21
20
19
18
17
16
–
–
–
–
–
–
–
–
15
14
13
12
11
10
9
8
–
–
TIMEOUT
DS
TCSR
7
6
5
4
3
2
1
0
–
PASR
–
–
LPCB
00
Low Power Feature is inhibited: no Power-down, Self-refresh or Deep Power-down command is issued to
the SDRAM device.
01
The SDRAM Controller issues a Self-refresh command to the SDRAM device, the SDCLK clock is
deactivated and the SDCKE signal is set low. The SDRAM device leaves the Self Refresh Mode when
accessed and enters it after the access.
10
The SDRAM Controller issues a Power-down Command to the SDRAM device after each access, the
SDCKE signal is set to low. The SDRAM device leaves the Power-down Mode when accessed and
enters it after the access.
11
The SDRAM Controller issues a Deep Power-down command to the SDRAM device. This mode is
unique to low-power SDRAM.
32058K
AVR32-01/12