pTAL Conversion Guide

ManualsBrandsHP ManualsServerHP Integrity NonStop H-Series

100

Pointers

pTAL Conversion Guide—527302-002

10-23

Converting Between Address Types

•

$WADDR_TO_BADDR(x)

•

$WADDR_TO_EXTADDR(x)

These routines are described in Section 17, TAL Standard Routines.

The $DBL and $INT routines accept address arguments.

$DBL accepts an EXTADDR address as an argument and converts it to a 32-bit

integer.

$INT accepts a variable whose data type is any of SGBADDR, SGWADDR,

SGXBADDR, and SGXWADDR as an argument, and returns a 16-bit integer. No other

address types can be used as an argument to $INT.

For more information about $DBL and $INT see Section 17, TAL Standard Routines.

Low-Level Address Conversions Using Arithmetic

Operations

You can convert between address types using shift operations and low-level routines.

These conversions are supported in pTAL for compatibility with TAL programs. Use the

equivalent pTAL routine when you write new pTAL code.

Table 10-7 on page 10-23 shows all low-level conversions as well as the equivalent

built-in routines. For example, in the first three conversions, you can use only a logical

shift, you must shift by exactly one bit, and you must use a left shift for a word-oriented

address to a byte-oriented address, and a right shift for a byte-oriented address to a

word-oriented address.

The following examples show valid and invalid shifts of addresses:

Table 10-7. Low-Level Conversions Between Address Types

Expression Type of Operand Built-In Routine

e ‘<<‘ 1

WADDR

SGWADDR

SGXWADDR

$WADDR_TO_BADDR(e)

$SGWADDR_TO_SGBADDR(e)

e ‘>>‘ 1

BADDR

SGBADDR

SGXBADDR

$BADDR_TO_WADDR(e)

$SGBADDR_TO_SGWADDR(e)

$UDBL(e)

$DBLL(0,e)

BADDR

$BADDR_TO_EXTADDR(e)

$UDBL(e) ‘<<‘ 1

$DBLL(0,e) ‘<<‘ 1

WADDR

$WADDR_TO_EXTADDR(e)