W65C832_1 Datasheet, PDF (23/64 Pages) –

WDC
THE WESTERN DESIGN CENTER, INC.
W65C832
SECTION 3
ADDRESSING MODES
The W65C832 is capable of directly addressing 16 MBytes of memory for program space
and 4GBytes for data space although only 24 bits (16MBytes) of address space are
available on the standard product. This address space has special significance
within certain addressing modes, as follows:
3.1 Reset and Interrupt Vectors
The Reset and Interrupt Vectors use the majority of the fixed addresses between
OOFFDO and OOFFFF.
3.2 Stack
The Stack may use memory from 000000 to OOFFFF. The effective address of Stack and
Stack Relative addressing modes will be always be within this range.
3.3 Direct
The Direct addressing modes are usually used to store memory registers and pointers.
The effective address generated by Direct, Direct,X and Direct,Y addressing modes is
always in Bank 0 (OOOOOO-OOFFFF).
3.4 Program Address Space
The Program Bank register is not affected by the Relative, Relative Long, Absolute,
Absolute Indirect, and Absolute Indexed Indirect addressing modes or by incrementing
the Program Counter from FFFF. The only instructions that affect the Program Bank
register are: RTI, RTL, JML, JSL, and JMP Absolute Long. Program code may exceed
64K bytes although code segments may not span bank boundaries.
3.5 Data Address Space
The Data Address space is contiguous throughout the 16 MByte address space. Words,
arrays, records, or any data structures may span 64 KByte bank boundaries with no
compromise in code efficiency. The following addressing modes generate 24-bit
effective addresses in W65C816 Emulation mode and some, where noted by (*), generate
32-bit effective address in W65C832 native mode.
o Direct Indexed Indirect (d,x)
* Direct Indirect Indexed (d),y
o Direct Indirect (d)
o Direct Indirect Long [dl
* Direct Indirect Long Indexed [dl,y
o Absolute a
* Absolute a,x
* Absolute a,y
o Absolute Long al
* Absolute Long Indexed al,x
* Stack Relative Indirect Indexed (d,x),y
MARCH 1990
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