Datasheet

416
AT32UC3A
Figure 28-4. SDRAM Device Initialization Sequence
28.6.2 I/O Lines
The pins used for interfacing the SDRAM Controller may be multiplexed with the PIO lines. The
programmer must first program the PIO controller to assign the SDRAM Controller pins to their
peripheral function. If I/O lines of the SDRAM Controller are not used by the application, they
can be used for other purposes by the PIO Controller.
28.6.3 Interrupt
The SDRAM Controller has an interrupt line connected to the interrupt controller. In order to han-
dle interrupts, the interrupt controller must be programmed before configuring the SDRAM
Controller.
Using the SDRAM Controller interrupt requires the IC to be programmed first.)
SDCK
SDRAMC_A[9:0]
A10
SDRAMC_A[12:11]
SDCS
RAS
CAS
SDWE
NBS
Inputs Stable for
200 μsec
Precharge All Banks 1st Auto-refresh 8th Auto-refresh MRS Command Valid Command
SDCKE
t
RP
t
RC
t
MRD
32058K
AVR32-01/12