memcpy

MemCpy( [address1 source], [byte1 offset], [address2 destination], [byte2 total] );

• [address1 source] - Source address to copy from
• [byte1 offset] - offset to start copying from
• [address2 destination] - destination address to copy to
• [byte2 total] - number of bytes to copy

Description

Copies 0-255 (parameter 4) bytes of memory from source address (parameter 1 + parameter 2) to destination address (parameter 3).

Example

// copies 40 bytes of data from my_data to the first row of the screen (bank 0) MemCpy(my_data, 0, ^$0400,40);

MemCpy also supports copying with zero pages:

// copies 160 bytes = 4 rows from color memory to some user-defined pointer MemCpy(^$D800, 0, my_ptr, 160);

Notes:

MemCpy is the slowest. It copies 0-256 bytes from A to B by basically (in assembler) saying

This is slow because for every copied byte, it needs to decrement i and test if it is zero and go to the top again

for i:=0 to 256 do B[i] := A[i];