🚀 go-pugleaf

In <+|#@byu.edu> $dougn@sasb.byu.edu writes:

> Hi there, fellow warriors!

Hi.

> What is the maximum value a DAT can hold?

The size of the core minus one.  Therefore, this will vary depending on
what coresize you're playing with - for example in a coresize of 8192,
the maximum value would be 8191, and in a coresize of 8000, the maximum
value would be 7999.  These would both be treated as -1 for all practical
purposes.  However, this does not mean that you cannot add a number to
this value; the result will be the remainder gotten after division by the
coresize.  For instance, adding 456 to 7999 in a coresize of 8000 would
give you 8455, which gets turned into 455.

> Also, what 
> does DAT #0, #0 do?  (How can a DAT hold two values?)

It doesn't do anything, except kill any process that tries to execute it.
DATs have A-  and B-fields just like all other Redcode instructions,
however "ADD #x, y", "SUB #x, y", and pre-decrement only change the B-field.
To change the A-field, you need to add or subtract an entire instruction to
the DAT, like "ADD x, y" or "SUB x, y".  Also, indirect addressing uses only
the B-field.  For these reasons, when DATs are used as pointers, it is often
easier to use only the B-field and ignore the A-field.

Kent Peterson