TC1796
Peripheral Units (Vol. 2 of 2)
Micro Link Interface (MLI)
User’s Manual
23-47
V2.0, 2007-07
MLI, V2.0
23.2.2.5 Memory Access Protection
The MLI receiver provides a memory access protection logic allowing to exclude read
and write accesses of the MLI move engine to specific parts of the memory map from
automatic mode. Each address of a data move (read or write) is always checked if it
targets an address range that is enabled for read/write access. If a requested data move
is targeting an excluded address range, a memory access protection error event is
generated and the receiving controller’s software can take care of the service request.
The memory access protection logic handles two levels of address range definitions:
•
Fixed address ranges (for complete modules or memory areas)
•
Programmable address sub-ranges (to limit accesses to specific parts of bigger
memory areas)
There is a maximum of 32 fixed address ranges available that can be individually
enabled/disabled by the address range enable bits AER.AENx (x = 0-31). If bit
AER.AENx is set, read/write accesses to the associated address range x are supported
in automatic mode. If bit AENx is cleared, read/write accesses to the associated address
range x are not automatically executed, a memory protection error event is generated,
and SRx output line is activated if enabled by RISR.MPEI.
The MLI module supports a definition of up to four programmable address sub-ranges
(with index n) within fixed address ranges. The parameters for the sub-ranges are stored
in the access range register ARR, comprising:
•
The size of an address slice defined as sub-range (ARR.SIZEn)
•
The location of an address slice defined as sub-range (ARR.SLICEn)
Note: The definition of the fixed address ranges and the sub-ranges is product-specific
and given in