pTAL Conversion Guide

Data Representation

pTAL Conversion Guide—527302-002

4-7

Data in System Global Variables

The address type of pointers to system global variables is one of SGBADDR,

SGWADDR, SGXBADDR, or SGXWADDR.

TAL

.SG pointers point to system global variables.

pTAL

Both .SG and .SGX pointers point to system global variables.

pTAL allocates 16 bits for .SG pointers and 32 bits for .SGX pointers:

STRING .SG s; ! s is 16 bits for both pTAL and TAL

INT .SG i; ! i is 16 bits for both pTAL and TAL

STRING .SGX s; ! s is 32 bits for pTAL, not available in TAL

INT .SGX i; ! i is 32 bits for pTAL, not available in TAL

If you share pTAL source files with TAL programs that include pointers to system

globals, use .SG pointers.