Currently, there are no FRAM devices with >64k.
However, the existing demo projects and the linker default put the stack in 
FRAM area.
(Yes, I was surprised too, as there are 2k RAM)
I didn't dig deeper in it, but you can mor eor less define which part of FRAM 
shall be
protected and which one is R/W (without waitstates!)

About flash, no, you don't need the BSL or the external JTAG.
The MSP can reprogram its flash at runtime.
Eithe ryou have the code running in ram, or during an erase or write
operation, the CPU will fetch a JMP $ statement (0x3fff) instead of the
real next instruction.
The only important thing is thatz ionterrupts (including NMI) need to be
disabled as the CPU would fetch 0x3fff as the interrupt vector too.
(Unless you have the vector table moved to ram, as you can do
with the 5x devices)

However, you need to unlock flash for writing first, and on older MSPs, you 
have to
program the clock source for the flash controller too.

In fact, the JTAG just injects some ram-based code that contains the data and
write code into the MSP ram and executes it.
(see the -r option for msp430-jtag, it defines how much space is used per such
program run for data)

The info memory is just the same, only that it is not counted to the flash pool 
for
code placing, and has smaller segments, so you don't have to 
read-modify-erase-write full 512 bytes if you want to update a single datum in 
it.
Except for the segment size, the code needed for handling info and main flash
is identical.

JMGross

----- Ursprüngliche Nachricht -----
Von: Peter Bigot
An: Alex Stefan
Gesendet am: 05 Aug 2011 13:05:33
Betreff: Re: [Mspgcc-users] How to access 20 bit peripheral registers...

Based on what I tried with your example yesterday, mspgcc generates
the code as you've written it, but it probably doesn't do what you
intended.

>From my experience, only the relatively small RAM section (and the
really tiny information memory blocks) can be written with standard
MSP430 instructions like this.  I'm not aware of any existing MSP430
parts that have RAM above the 64KB boundary.

Anything in high memory will be read-only: the flash memory requires
an external JTAG programmer or the bootstrap loader special to be
writable  See 
http://focus.ti.com/mcu/docs/litabsmultiplefilelist.tsp?sectionId=96&tabId=1502
&literatureNumber=slau265j&docCategoryId=6&familyId=342

I don't know how the new FRAM parts work, but I expect they still
require some sort of configuration to enable writes.

Peter


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