Atmel ARM-Based Evaluation Kit for SAM4S16C, 32-Bit ARM® Cortex® Microcontroller ATSAM4S-WPIR-RD ATSAM4S-WPIR-RD Data Sheet

Product codes
ATSAM4S-WPIR-RD
Page of 1231
SAM4S Series [DATASHEET]
Atmel-11100G-ATARM-SAM4S-Datasheet_27-May-14
440
26.3
I/O Lines Description
26.4
Product Dependencies
26.4.1 I/O Lines
The pins used for interfacing the Static Memory Controller are multiplexed with the PIO lines. The programmer 
must first program the PIO controller to assign the Static Memory Controller pins to their peripheral function. If I/O 
Lines of the SMC are not used by the application, they can be used for other purposes by the PIO Controller.
26.4.2 Power Management
The SMC is clocked through the Power Management Controller (PMC), thus the programmer must first configure 
the PMC to enable the SMC clock.
26.5
External Memory Mapping
The SMC provides up to 24 address lines, A[23:0]. This allows each chip select line to address up to 16 Mbytes of 
memory. 
If the physical memory device connected on one chip select is smaller than 16 Mbytes, it wraps around and 
appears to be repeated within this space. The SMC correctly handles any valid access to the memory device 
within the page (se
). 
Table 26-1.
I/O Line Description
Name
Description
Type
Active Level
NCS[3:0]
Static Memory Controller Chip Select Lines
Output
Low
NRD
Read Signal
Output
Low
NWE
Write Enable Signal
Output
Low
A[23:0]
Address Bus
Output
D[7:0] Dat
a Bus
I/O
NWAIT
External Wait Signal
Input
Low
NANDCS
NAND Flash Chip Select Line
Output
Low
NANDOE
NAND Flash Output Enable
Output
Low
NANDWE
NAND Flash Write Enable
Output
Low