> I understand that there are three separate storage areas:  program
> memory, data memory, and a small bit of EEPROM memory.   It is my
> understanding
> from the datasheet that all of the instructions which move data to or
> from storage (that is, the instructions which involve "f") strictly
> operate to
> or from data memory (RAM).

Yes, except when the source is a literal.  The literal value comes from
the instruction word, and therefore from program memory.

> It also appears to me that to pre-allocate storage in assembler
> language,
> that one uses the CBLOCK directive,

CBLOCK and the associated absolute mode are evil.  All new code should be
using relocatable mode and the linker.  In relocatable mode, you define a
UDATA or similar section, then use the RES directive to allocate RAM.

> How does one read/write the data allocated in data memory?

As you said above, instruction that operate on F (file registers).

> How does one pre-allocate storage in EEPROM memory.  Is this what the DE
> directive is for?

Yes, together with the right linker section to locate the result in the
part of the HEX file (not PIC) address space reserved for EEPROM initial
data.

> And same question as to how to read/write it.

There is a special "peripheral" for accessing the EEPROM at run time.  See
manual.


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