ARM Cortex R4F Benutzerhandbuch

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Level One Memory System 
ARM DDI 0363E
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8.4.2
ATCM and BTCM configuration
The TCM interfaces are configured during implementation and integration.
You can configure the ATCM interface to be removed, and not included in the processor design. 
If implemented, the ATCM can have only a single port.
You can configure the BTCM interface to:
be removed, and not included in the processor design
have a single BTCM port
have two banked BTCM ports, interleaved on either:
Bit [3] of the address
The most significant bit of the BTCM interface address. This depends on the size of 
the BTCM.
During implementation, you can configure the ATCM and/or the BTCM to use an 
error-protection scheme to protect the data stored in the TCM, see TCM internal error detection 
and correction
.
The size of each TCM interface is configured during integration. See the Cortex-R4 and 
Cortex-R4F Integration Manual
 for more information. The permissible TCM sizes are:
0KB
4KB
8KB
16KB
32KB
64KB
128KB
256KB
512KB
1MB
2MB
4MB
8MB.
If the BTCM interface has two ports, the size of the RAM attached to each port is half the total 
size for the BTCM interface.
The size of the TCM interfaces is visible to software in the TCM Region Registers, see c9, 
BTCM Region Register
 on page 4-57 
and c9, ATCM Region Register on page 4-58. All TCM 
interface build configuration options can be read from the Build Options Registers, see c15, 
Build Options 1 Register
 on page 4-72 and c15, Build Options 2 Register on page 4-72
.
8.4.3
TCM internal error detection and correction
Each TCM interface can be configured with either parity, 32-bit ECC, or 64-bit ECC error 
schemes. Both the BTCM ports must have the same error scheme. The following sections 
describe these error schemes: