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Format
Example
N
140
N+Rn
332+R5
(An)
(A1)
(d,An)
(120,A1)
or
120(A1)
d(An)
(d,An,Xn)
(&120,A1,D2)
or
&120(A1,D2)
d(An,Xn)
N - Absolute address (any valid expression)
Dn - Data register n
An - Address register n
Xn - Index register n (An or Dn) d Displacement (any valid expression)
bd - Base displacement (any valid expression) n Register number (0 to 7)
Rn - Offset register n
ZXn - Zero suppressed register Xn
2.2.1.3 Offset Registers
Eight pseudo-registers (R0 through R7) called offset registers are used to simplify the debugging
of re-locatable and position-independent files. These files when listed have a starting address
(normally 0), but when loaded into memory, due to the offset registers, they are loaded into a
different memory location. Implementing offset registers makes it harder to correlate addresses in
the listing with addresses in the loaded program. The offset registers solve this problem by taking
into account this difference and forcing the display of addresses in a relative address+offset
format. The range for each offset register is set by two addresses: base and top. Specifying the
base and top addresses for an offset register sets its range. Offset registers have adjustable ranges
which may overlap. In the event that an address falls in two or more offset register ranges, the
one that yields the least offset is chosen.
Relative addresses are limited to 1 megabyte (5 digits), regardless
of the range of the closest offset register.
M68CPU32BUG/D REV 1
Table 2-1. Debugger Address Parameter Format
Absolute address+contents of automatic offset register.
Absolute address+contents of the specified offset register (not an
assembler-accepted syntax).
Address register indirect.
Address register indirect with displacement (two formats accepted).
Address register indirect with index and displacement (two formats
accepted).
Symbol Definition
Description
NOTE
2-5
DEBUG MONITOR DESCRIPTION
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