Technical data

SDA Description
7.2.1 Radix Operators
Radix operators determine which numeric base SDA uses to evaluate
expressions. You can use one of three radix operators to specify the radix of
the numeric expression that follows the operator:
• ^X (hexadecimal)
• ^O (octal)
• ^D (decimal)
The default radix is hexadecimal. SDA displays hexadecimal numbers with
leading zeros and decimal numbers with leading spaces.
7.2.2 Arithmetic and Logical Operators
There are two types of arithmetic and logical operators, both of which are listed
in Table SDA–8.
• Unary operators affect the value of the expression that follows them.
• Binary operators combine the operands that precede and follow them.
In evaluating expressions containing binary operators, SDA performs logical
AND, OR, and XOR operations, and multiplication, division, and arithmetic
shifting before addition and subtraction. Note that the SDA arithmetic operators
perform integer arithmetic on 32-bit operands.
Table SDA–8 SDA Operators
Operator Action
Unary Operators
# Performs a logical NOT of the expression
+ Makes the value of the expression positive
– Makes the value of the expression negative
@ Evaluates the following expression as a virtual address, then uses the
contents of that address as value
G Adds 80000000
16
to the value of the expression
1
H Adds 7FFE0000
16
to the value of the expression
2
Binary Operators
+ Addition
– Subtraction
* Multiplication
& Logical AND
| Logical OR
\ Logical XOR
1
The unary operator G corresponds to the first virtual address in system space. For example, the
expression GD40 can be used to represent the address 80000D40
16
.
2
The unary operator H corresponds to a convenient base address in the control region of a process
(7FFE0000
16
). You can therefore refer to an address such as 7FFE2A64
16
as H2A64.
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SDA–16