Epson S5U1C17001C, Manual

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S5U1C17001C ManUal
EPSOn
3-25
(C COMPilEr PaCkagE fOr S1C17 faMily) (Ver. 1.5.0)
3 SOfTWarE DEVElOPMEnT PrOCEDUrES
3
SoftDev
You'll see that the five basic sections (output sections)—i.e.,
.bss
,
.data
,
.vector
,
.text
, and
.ro-
data
—are preset in the Section name column.
.bss
Section in which variables without initial values are placed. (Normally located in
RAM.)
.data
Section in which variables with initial values are placed. (The initial values are lo-
cated in ROM. They are copied into RAM when needed.)
.vector
Section in which vector tables are placed. (The actual data is located in ROM.)
.text
Section in which program codes are placed. (The actual data is located in ROM and
executed there or from high-speed RAM after copying.)
.rodata
Constant variables. (The actual data is located in ROM.)
The VMA (Virtual Memory Address) is the position (start address) at which a section is placed during runtime.
If a section does not have its start address indicated in the VMA column, it means that the section is to be lo-
cated following the immediately preceding section.
The LMA (Load Memory Address) is the position (start address) in ROM at which the actual data is placed.
If this column is marked with "-", it means that this address is the same as the VMA (i.e., the section will be
executed or accessed at the position at which the actual data is placed). If this column is marked with "
after
(.rodata)
", it means that the actual data is to be located following the section indicated in parentheses (in
this case, the
.rodata
section).
The Labels column shows the labels indicating the start and end addresses of an area in which the section will
be located. If the LMA is not specified, two labels
<beginning of VMA> and <end of VMA> are shown here. If
the LMA is specified, four labels are shown in order of <beginning of VMA> , <end of VMA> , <beginning of
LMA>, and <end of LMA> . These labels may be used to specify addresses in a source file when, for example,
copying sections from ROM to RAM.
During actual program development, user defined sections can be added using the [Add] button.