ARM VERSION 1.2 - Manual (Page 67)

Writing ARM and Thumb Assembly Language
ARM DUI 0068B Copyright © 2000, 2001 ARM Limited. All rights reserved. 2-55
2.10.4 Finding the end of the allocated data
You can use the FIELD directive with an operand of 0 to label a location within a
structure. The location is labeled, but the location counter is not incremented.
The size of the data structure defined in Example 2-19 depends on the values of
MaxStrLen and ArrayLen . If these values are too large, the structure overruns the end of
available memory.
Example 2-19 uses:
• an EQU directive to define the end of available memory
• a FIELD directive with an operand of 0 to label the end of the data structure.
An ASSERT directive checks that the end of the data structure does not overrun the
available memory.
Example 2-19
StartOfData EQU 0x1000
EndOfData EQU 0x2000
MAP StartOfData
Integer FIELD 4
Integer2 FIELD 4
String FIELD MaxStrLen
Array FIELD ArrayLen*8
BitMask FIELD 4
EndOfUsedData FIELD 0
ASSERT EndOfUsedData <= EndOfData