DCB - Define Constant Block

  [<label>:]  DCB [.<size>] <count>, <value>
  
  

  <size> = 
  B (default), 
  W, or 
  L.

  

The DCB directive causes the Assembler to allocate a memory block initialized with the specified <value>. The length of the block is <size> * <count>.

<count> may not contain undefined, forward, or external references. It may range from 1 to 4096.

The value of each storage unit allocated is the sign-extended expression <value>, which may contain forward references. The <count> cannot be relocatable. This directive does not perform any alignment.

The following rules apply to size specifications for DCB directives:

• DCB.B: One byte is allocated for numeric expressions.
• DCB.W: Two bytes are allocated for numeric expressions.
• DCB.L: Four bytes are allocated for numeric expressions.
  Listing: Examples of DCB directives

  
  000000 FFFF FF     Label: DCB.B 3, $FF
  000003 FFFE FFFE          DCB.W 3, $FFFE
  
  000007 FFFE
  
  000009 0000 FFFE          DCB.L 3, $FFFE
  
  00000D 0000 FFFE
  
  000011 0000 FFFE
  

Assembler directives :

• DC - Define Constant
• DS - Define Space
• ORG - Set Location Counter
• SECTION - Declare Relocatable Section