Epson S5U1C62000A - Manual (Page 113)

S5U1C62000A MANUAL EPSON 101
(S1C60/62 FAMILY ASSEMBLER PACKAGE)
CHAPTER 6: LINKER
test1.o
CODE1 (relocatable)
BSS1 (relocatable)
CODE2 (absolute 0x000–)
BSS2 (absolute 0xe00–)
test.abs
ROM area
RAM area
CODE2
0x0000
0x0110
0x000
0x500
0x600
0xe00
0xf00
0x010f
0x1fff
0x4ff
0x5ff
0xdff
0xeff
0xfff
CODE3
CODE4
CODE1
BSS1
BSS2
BSS3
BSS4
test2.o
CODE3 (relocatable)
BSS3 (absolute 0xf00–)
CODE4 (relocatable)
BSS4 (relocatable)
Fig. 6.10.2 Example of linking
The absolute sections CODE2, BSS2 and BSS3 are mapped to the location specified in the source files.
The start addresses of the relocatable sections in "test2.o" is specified by the -rcode and -rbss options,
so CODE3 is mapped from address 0x110 and CODE 4 follows CODE3. BSS4 is mapped from address
0x600.
Since the start addresses of the relocatable CODE and BSS sections in "test1.o" have not been specified,
they are mapped from the relocatable section start addresses specified by the -code and -bss options.
First the linker will try to map CODE1 from address 0x0100 to address 0x010f. If CODE2 is smaller
than 0x100 words and CODE 1 is smaller than 0x10 words, CODE1 can be mapped from address
0x0100. In this example, CODE1 is mapped behind CODE4 because CODE1 is larger than 0x10 words.
When the -or option is specified, the linker will try to map CODE1 in the same page as one of the
already mapped sections that has many branching relationships.
BSS1 is mapped from address 0x500, however it may be mapped behind BSS4 if BSS1 is larger than
0x100 words.
A section cannot be overlapped to other sections, therefore an error will occur if there is no free area
larger than the section size. For example, an error will occur if CODE2 is larger than 0x110 words.