Using the write function and overwriting variables

Archiver

If you use a write function on say slot 4 could you mistakenly
overwrite memory on slot 3.
Thanks,
Jack Lindsay

Archiver

In a message dated 4/20/2004 3:26:40 PM Eastern Daylight Time,
jlindsay24@y... writes:


> If you use a write function on say slot 4 could you mistakenly
> overwrite memory on slot 3.
>

Each slot has 2K memory. You can use the lower portion of memory on any slot
without endangering data written to the same area in other slots.


Sid Weaver
We're always thinking.....
http://www.visualmuses.com/chipcircuit/index.html





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Archiver

>If you use a write function on say slot 4 could you mistakenly
>overwrite memory on slot 3.
>Thanks,
>Jack Lindsay

I think you are asking this with respect to a BS2p.

You would certainly not overwrite the memory in slot 3 once you have
issued the STORE 4 command. Once you have issued the STORE 4
command, all subsequent writes will be to slot 4 until, 1) you issue
a STORE n command to a different slot or 2) you issue a RUN command
to move program execution to another slot.

When you issue a RUN command, the storage follows suit, and initially
writes will be to that same bank as was RUN. You then need a STORE n
command to point the READS and WRITES to another bank.

You can implement bank-neutral subroutines. For example, suppose you
need a subroutine to store something in bank 4, but you want this
subroutine not to affect the STORage pointer that is in effect when
the subroutine is called:
my_subroutine:
GET 127, holderVar ' reads the current store and run status
STORE 4
PUT location, mydata
STORE holderVar.NIB1 ' restores the entry STORE bank status
RETURN

You didn't ask about that, but know that location 127 in the
scratchpad is read-only, and always contains the current RUN and
STORE banks in nib0 and nib1 respectively.

One of your initial questions was about using the BS2e as a data
logger, and now you are looking at the BS2p. Take a look too at the
BS2pe, because it has even more memory, 32k compared to 16k in the
BS2p, and other features that are great for data logging.
<http://www.emesystems.com/BS2pe.htm> .

-- Tracy