DenCop wrote:


>>>Maybe it's a stupid question, but how can I read/write external memory
>>>with a msp430. I have to store something like 15kB (not much).
>>>I thought about FIFO memory, because I think that will be the easiest
>>>way.
> 
> I used 8 pins so I have 6 pins over.  But what do you mean about external 
> hardware? 
> Do you have a name of a firm that makes FIFO memory, when I look on the 
> internet I don't get good results...

A lot depends on how you are using the memory. If you need quick random 
access, you're a bit stuck with only that IO left. But another post 
suggested I2C or similar serial memory, and if you don't need to access 
it too fast you can bit-bang this with 2 or 3 lines. For even less IO 
usage, but a messier solution, Dallas used to make 1 wire serial RAMs.

If you are reading and writing frequently, choose FERAM rather than 
EEPROM to avoid the write limit.

Paul Burke

"DenCop" <msp430@dencop.com> wrote in message
news:d3a06d83.0403240651.3e89a2ca@posting.google.com...
> Hi hello,
>
> Maybe it's a stupid question, but how can I read/write external memory
> with a msp430. I have to store something like 15kB (not much).
> I thought about FIFO memory, because I think that will be the easiest
> way.
>

Forget the idea of looking for a FIFO memory - these chips are specialist
devices for very high speed buffers.  It would be far more practical to use
a random-access memory of some sort and keep track of the start and end of
the FIFO in software.

Have a look for SPI or perhaps I2C bus memories to minimise pin counts.

DenCop wrote:
> Hi hello,
> 
> Maybe it's a stupid question, but how can I read/write external memory
> with a msp430. I have to store something like 15kB (not much).
> I thought about FIFO memory, because I think that will be the easiest
> way.

FIFO (First in First out) memory is normally used for elastic buffers.
Sounds like you need Serial memory, and Serial RAM is rare, but
Serial EE, or Serial FeRAM can be used as SRAM.
Depends on your read/write requirements.

Look at http://www.ramtron.com, and their 24C i2c devices, or new 25W256

>I used 8 pins so I have 6 pins over.  But what do you mean about external 
>hardware? 
>Do you have a name of a firm that makes FIFO memory, when I look on the 
>internet I don't get good results...
>

I just used Google using "FIFO" and saw iDT's FIFOs listed. I'm sure there are
other companies out there.

As for external hardware, I mean perhaps using a serial-parallel register
between your MSP and a FIFO. You'd shift your data bit by bit into the shift
register, then let it enter the data into the FIFO. I think I may have seen
FIFOs that already had that built-in though I'm not sure they were as big as
you'd need.

garykato@aol.com (Gary Kato) wrote:
>>Maybe it's a stupid question, but how can I read/write external memory
>>with a msp430. I have to store something like 15kB (not much).
>>I thought about FIFO memory, because I think that will be the easiest
>>way.
>
>How many I/O pins do you have free for talking to a device? Find a FIFO
>datasheet and see what is required. If you don't have enough free pins, you
>might have to use some external hardware or use a serial protocol like I2C or
>SPI.

I used 8 pins so I have 6 pins over.  But what do you mean about external 
hardware? 
Do you have a name of a firm that makes FIFO memory, when I look on the 
internet I don't get good results...

Thnx for your answer,

DenCop

>Maybe it's a stupid question, but how can I read/write external memory
>with a msp430. I have to store something like 15kB (not much).
>I thought about FIFO memory, because I think that will be the easiest
>way.

How many I/O pins do you have free for talking to a device? Find a FIFO
datasheet and see what is required. If you don't have enough free pins, you
might have to use some external hardware or use a serial protocol like I2C or
SPI.

Hi hello,

Maybe it's a stupid question, but how can I read/write external memory
with a msp430. I have to store something like 15kB (not much).
I thought about FIFO memory, because I think that will be the easiest
way.

I hope you can help me,

DenCop

PS sorry for my bad English