Hi,

How fast are the events you are trying to log? How do you know when the
event will occur/has occured to know to log it? How many do you need to log
(how big does your buffer need to be?)

In my design for a PIC-based DSO that I have been doing on and off for a
while now, I interfaced a PIC to a fast SRAM. In fact, the writes to the
SRAM were going on faster than the PIC could handle. The address was being
given by a fast synchronous counter IC and the PIC merely started/stopped
acquisition and read out the SRAM contents to a PC over a parallel port.

I think something like this would handle almost any high speed source of data.

Sean

At 09:03 PM 7/4/99 +0000, you wrote:
>I would be thankful if any engineer on the list could give me a
>basic background theory on how to implement logging of reasonably
>fast events using an mcu.(Or at least a reference on  the web)
> My problem is that the information I wish to log is received so fast
>that mcu ram and eeprom is overflowed. On the other hand if I use an
>external eeprom as backup I miss information while storing on it.
> What's the usual mechanism applied to this kind of devices?
>(Adding an external RAM mybe?)
>
>Thank you very much.
>------------------------------------
>netQ <netquake@innocent.com>
>http://virtuaweb.com/picprog
>"Home of amateur PIC programmers..."
>
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|
| Sean Breheny
| Amateur Radio Callsign: KA3YXM
| Electrical Engineering Student
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