Atmel SAM4L Xplained Pro Evaluation Kit Atmel ATSAM4L-XPRO ATSAM4L-XPRO Data Sheet

Product codes
ATSAM4L-XPRO
Page of 173
77
42023ES–SAM–07/2013
ATSAM4L8/L4/L2
8.9
System Manager Access Port (SMAP)
Rev.: 1.0.0.0
8.9.1
Features
Chip Erase command and status
Cortex-M4 core reset source
32-bit Cyclic Redundancy check of any memory accessible through the bus matrix
Unlimited Flash User page read access
Chip identification register
8.9.2
Overview
The SMAP provides memory-related services and also Cortex-M4 core reset control to a debug-
ger through the Debug Port. This makes possible to halt the CPU and program the device after
reset.
8.9.3
Block Diagram
Figure 8-7.
SMAP Block Diagram
8.9.4
Initializing the Module
The SMAP can be accessed only if the CPU clock is running and the SWJ-DP has been acti-
vated by issuing a CDBGPWRUP request. For more details, refer to the ARM Debug Interface
v5.1 Architecture Specification.
Then it must be enabled by writing a one to the EN bit of the CR register (CR.EN) before writing
or reading other registers. If the SMAP is not enabled it will discard any read or write operation. 
8.9.5
Stopping the Module
To stop the module, the user must write a one to the DIS bit of the CR register (CR.DIS). All the
user interface and internal registers will be cleared and the internal clock will be stopped.
SMAP Core reset request
DAP Bus
System 
Bus Matrix
AHB
chip_erase
Flash
Controller
AHB
SMAP
Ahb_Master
Core
DAP 
Interface
Reset
Controller
PM
Cortex-M4 core reset
System reset