Difference between revisions of "84PCE:Syscalls:0210E0"

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[[Category:84PCE:Syscalls:By_Name:Memory|MemSet]]
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[[Category:84PCE:Syscalls:By Name:Memory|MemSet]]
[[Category:84PCE:Syscalls:By_Name|MemSet]]
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[[Category:84PCE:Syscalls:By Name|MemSet]]
[[Category:84PCE:Syscalls:By_Address|0210E0 - MemSet]]
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[[Category:84PCE:Syscalls:By Address|0210E0 - MemSet]]
  
 
== Synopsis ==
 
== Synopsis ==
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=== Destroys ===
 
=== Destroys ===
* AF, BC, HL
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* HL = HL+BC
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* DE = HL+1+BC
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* BC = 0
  
 
== Comments ==
 
== Comments ==
 
This routine uses an LDIR instruction to clear the memory block, so do not pass it a block length of 0 or 1 or it will erase 16777216 bytes.
 
This routine uses an LDIR instruction to clear the memory block, so do not pass it a block length of 0 or 1 or it will erase 16777216 bytes.
''See Also: [[Category:84PCE:Syscalls:By_Name|MemClear]]''
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''See also: [[84PCE:Syscalls:0210DC|MemClear]]''
  
 
== Example ==
 
== Example ==

Latest revision as of 02:45, 16 July 2016


Synopsis

Official Name: MemSet

Syscall Address: 0210E0h

Sets a block of memory to the value in A.

Inputs

  • HL: Address of memory block.
  • BC: Number of bytes to zero.
  • A: Value to set memory block to.

Outputs

  • DE: Points to byte after memory block.

Destroys

  • HL = HL+BC
  • DE = HL+1+BC
  • BC = 0

Comments

This routine uses an LDIR instruction to clear the memory block, so do not pass it a block length of 0 or 1 or it will erase 16777216 bytes.

See also: MemClear

Example

      ;Clear out pixelShadow with spaces
      ld     a,' '
      ld     hl,pixelShadow
      ld     bc,8400
      call   _MemSet