Epson S5U1C17001C, Руководство пользователя

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S5U1C17001C ManUal
EPSOn
5-131
(C COMPilEr PaCkagE fOr S1C17 faMily) (Ver. 1.5.0)
5 gnU17 iDE
5
IDE
Unused
.data (2)
.data (3)
.bss (2)
.bss (3)
.data (1)
.data (1) .text (1)
.rodata (1)
vector.o
(when vector.o, main.o, and libc.a are linked)
.bss (1)
.data (2)
.rodata (2)
.text (2)
main.o
.bss (2)
.data (3)
.rodata (3)
.text (3)
libc.a (library)
.bss (3)
.bss (1)
(RAM)
Copied
before
use
.data
section
(VMA)
.bss
section
(VMA)
0x000000
__END_data
__START_data
__END_bss
__START_bss
Unused
.text (2)
.text (3)
.text (1)
.rodata (2)
.rodata (3)
(ROM)
.data (2)
.data (3)
.data (1)
.data
section
(LMA)
.rodata
section
(LMA = VMA)
.text
section
(LMA = VMA)
.vector
section
(LMA = VMA)
0x008000
__START_data_lma
__END_rodata
__START_rodata
__END_text
__START_text
__END_vector
__START_vector
.rodata (1)
Figure 5.7.6.1 Selection location in default settings
As shown in the [Section name] column, the following five basic sections are set in advance:
.bss
: A section in which variables without initial values are placed. (This is normally lo-
cated in RAM.)
.data
: A section in which variables with initial values are placed. (The initial values are
located in ROM. When needed, they are copied into RAM.)
.vector
: A section in which vector tables are placed. (The actual data is located in ROM.)
.text
: A section in which program code is placed. (The actual data is located in ROM and
executed from there or from high-speed RAM after copying.)
.rodata
: Constants. (The actual data is located in ROM.)
The section information is displayed in blue except for the
.vector
section displayed in black. Blue is used to
display the standard sections defined by default and black is used to display other user defined sections. To edit
the section name, standard section attribute, address to locate, and objects to be located, a user section should
be created. The standard section allows the user to specify the location address only, and objects are automati-
cally located except those are located in the user sections with the same attribute.
The "VMA" (Virtual Memory Address) is the position (start address) at which a section is placed when ex-
ecuted. A section whose address is not written in the VMA will be located at an address following the section
immediately preceding.
The "LMA" (Load Memory Address) is the position in a ROM (start address) at which the actual data is locat-
ed. "-" means the same as the VMA (i.e., a section will be executed or accessed from the position at which its
actual data is placed). "
after(.rodata)
" means that a section will have its actual data located at an address
following another section (in this case, the
.rodata
section).
"Labels" are the labels indicating the start and the end addresses of the area in which a section will be located.
When a VMA is specified, two labels are displayed, whereas when a LMA is specified, four labels for the start/
end VMA addresses and the start/end LMA addresses are displayed, in that order. These labels can be used to
specify the address in a source file when (for example) a section is copied from ROM to RAM. The names of
these labels are automatically generated from section names.
Example:
__START_bss:__END_bss
Labels indicating the start and end addresses of a
.bss
section
__START_data:__END_data:__START_data_lma:__END_data_lma
Labels indicating the start VMA address, end VMA address, start LMA address, and end LMA ad-
dress of a
.data
section