Zilog EZ80F916 - Manual (Page 204)

UM014423-0607
ZiLOG Developer Studio II
eZ80Acclaim! ® User Manual
184
NOTE: The lowest and highest addresses are the lowest and highest possible addresses; the
C-Compiler uses the values in the preceding table as a default. However, the
hardware might not physically have all of the possible addresses, so you can use
ZDS II to set a different range.
Code and data are allocated to these spaces by using segments attached to the space.
Segments
Segments are used to represent regions of memory. Only one segment is considered active
at any time during the assembly process. A segment must be defined before setting it as
the currently active segment. Every segment is associated with one and only one address
space.
Segments are described in the following sections:
•
“Predefined Segments” on page 184
•
“User-Defined Segments” on page 185
Predefined Segments
For convenience, the segments listed in the following table are predefined by the assem-
bler. Each segment gets assigned to one of the address spaces in Table 7. If no address
space is associated with a segment, ROM is the default space. All of the predefined seg-
ments listed here can be aligned on any byte boundary.
INTIO I On-chip I/O address space. 00000000–
000000FF 256 bytes 1 byte
(8 bits)
EXTIO E External I/O address space. 00000000–
0000FFFF 64 KB 2 bytes
(16 bits)
Table 8. Predefined Segments
Segment Name Address Space Contents
__VECTORS ROM Constant data
STRSECT RAM Initialized strings
TEXT ROM Constant data
Table 7. eZ80Acclaim! Address Spaces (Continued)
Space ID
Display
Prefix
Description
Lowest and
Highest
Addresses
Size
Maximum That
Can Be Retrieved
at One Time