Configuration
10-7
TMS320C32 Enhanced External Memory Interface
10.3 Configuration
To access 8-, 16-, or 32-bit data (types) from 8-, 16-, or 32-bit wide memory, the
memory interface of the ’C32 device uses either strobe STRB0 or STRB1
with
four pins each. These pins serve as byte-enable and/or additional-address pins.
In conjunction with a shifted version of the internal address presented to the exter-
nal address, the ’C32 can select a single byte from one external memory location
or combine up to four bytes from contiguous memory locations. The behavior of
these pins is controlled by the external memory width and the data type size. The
selected data size also determines the amount of internal-to-physical address
shift. You can assign these values to the ’C32 memory interface through bit fields
in the bus control registers.
10.3.1 External Interface Control Registers
The following sections describe the bus control registers used to manipulate
the byte addressability features of the ’C32. Figure 10–3 shows the external
interface control memory map.
Figure 10–3. Memory-Mapped External Interface Control Registers
ÁÁÁÁ
ÁÁÁÁ
Address
ÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁ
Register
Á
Á
ÁÁÁÁ
ÁÁÁÁ
808060h
IOSTRB control
Á
Á
ÁÁÁÁ
ÁÁÁÁ
808061h
Reserved
Á
Á
ÁÁÁÁ
ÁÁÁÁ
808062h
Reserved
Á
Á
ÁÁÁÁ
ÁÁÁÁ
808063h
Reserved
Á
Á
ÁÁÁÁ
808064h
STRB0 control
Á
ÁÁÁÁ
ÁÁÁÁ
808065h
Reserved
Á
Á
ÁÁÁÁ
ÁÁÁÁ
808066h
Reserved
Á
Á
ÁÁÁÁ
ÁÁÁÁ
808067h
Reserved
Á
Á
ÁÁÁÁ
ÁÁÁÁ
808068h
STRB1 control
Á
Á
ÁÁÁÁ
ÁÁÁÁ
808069h
Reserved
Á
Á
ÁÁÁÁ
Á
ÁÁ
Á
Á
ÁÁ
Á
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁ
Á
ÁÁÁÁÁÁÁÁÁÁÁ
Á
Á
ÁÁÁÁÁÁÁÁÁÁÁ
Á
ÁÁÁÁÁÁÁÁÁÁÁÁÁ
.
.
.
Á
Á
Á
Á
ÁÁÁÁ
ÁÁÁÁ
80806Fh
Reserved
Á
Á
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁ
ÁÁÁÁÁÁÁÁÁÁÁÁÁ
Á
Á