Texas Instruments TMS320C54x, User Manual

Page: 334 / 469

Controlling the ROM Device Address
10-34
10.10 Controlling the ROM Device Address
The hex conversion utility output address field corresponds to the ROM device
address. The EPROM programmer burns the data into the location specified
by the hex conversion utility output file address field. The hex conversion utility
offers some mechanisms to control the starting address in ROM of each sec-
tion and/or to control the address index used to increment the address field.
However, many EPROM programmers offer direct control of the location in
ROM in which the data is burned.
10.10.1 Controlling the Starting Address
Depending on whether or not you are using the boot loader, the hex conversion
utility output file controlling mechanisms are different.
Nonboot-loader mode. The address field of the hex conversion utility output
file is controlled by the following mechanisms listed from low to high priority:
1) The linker command file . By default, the address field of the hex conver-
sion utility output file is a function of the load address (as given in the linker
command file) and the hex conversion utility parameter values. The rela-
tionship is summarized as follows:
out_file_addr
†
= load_addr (data_width mem_width)
out_file_addr is the address of the output file.
load_addr is the linker-assigned load address.
data_width is specified as 16 bits for the TMS320C54x devices.
See subsection 10.4.2,
Data Width, on page 10-10.
mem_width is the memory width of the memory system. You can
specify the memory width by the –memwidth option
or by the
memwidth parameter inside the ROMS
directive. See subsection 10.4.3, Memory Width, on
page 10-10.
† If paddr is not specified
The value of data width divided by memory width is a correction factor for
address generation. When data width is larger than memory width, the
correction factor
expands the address space. For example, if the load
address is 0 1 and data width divided by memory width is 2, the output file
address field would be 0 2. The data is split into two consecutive loca-
tions the size of the memory width.
2) The paddr parameter of the SECTIONS directive. When the paddr
parameter is specified for a section, the hex conversion utility bypasses