#8 ALU and RAM zero Manual

[Jeff Loeliger]

How the assembler decides if it should use an ALU or RAM zero instruction when reg = 0; is reguested needed to be explained in the manual.

email from Zoltan:
The idea was that the assembler works it out which way to do it,
depending on other operations performed by the ALU/memory. That is, if
you do an ALU operation, the the clear is done by a memory op, if you
do a memory op, then it's done by the ALU. I considered it the same
problem as when you write reg = 0; in which case it is an ALU operation
but it can be done by many different ways and instruction formats, so
it is up to the assembler to choose one. There is a preferential order:
for example, in case of zeroing p or diob the assembler would choose
ALU first (unless the ALU is already in use) and memory second, so in
your example diob would be loaded by ALU and p by memory (and go into
a single instruction).