Hi,

I have a problem with the transfer speed of data to a memory card during a burst. When the logger runs without a memory card inserted it takes about 10 sec. to log the data but if I have the memory card inserted it takes about 2min 50sec.

If the burst has been run without the memory card inserted until the internal memory is full it only takes a couple of seconds to transfer the data to the memory card when it is inserted. I am running the following program:

'JOB=JOB1 
'COMPILED=2005/04/25 07:41:17 
'deLogger generated program file for dataTaker 8 series 
DT=\d 
BEGIN"JOB1" CATTN 
'Spans and polynomial declarations 
S1=0,400,400,2000"bar" 
'Thermistor declarations 
'Switches declarations 
'Parameter declarations /b 
P15=2 P31=3 P54=0 P47=5 P48=100 P60=100 
'Global declarations 
'main schedule definitions 
RS1S 
'schedule definition 
RA1+E;BURST(3000,16000) LOGONA GA 
1V("Relay") 
2V("Valve") 
3V(S1,"Pressure") 
END 
'end of program file

Regards,
Per Skov

Good morning Per Skov,

It's the memory card that is slowing things down.
The internal memory of any computer system has much faster read / write times than a hard disk. Well the memory card is just like a hard disk, it is much slower than the internal memory. Some cards can have up to 100 mSec access time.

We have been looking into the access speeds of memory cards and have found a big variations in the write speeds of cards.

Which memory card is it?

Cheers,
Roger

Hello Roger,

It is an old 64MB CF card from Sandisk. I have now changed it to a 256MB from Kingston and the storage time is now down to 35 sec, and that is sufficient for my application.

Thanks for your help.

Per Skov

Hello.

My DT800 and memory card combo has the same problem, except it takes more than 5 minutes to write 10000 points. I am using a 1GB PNY P-CF1G-RF3 card that I bought yesterday at BestBuy but no detailed speed specifications were provided with the card.

My current firmware version is 4.08.0001. I'll check to see if it's the latest. I'll also check out the tech notes on CF cards.

Thanks much,
aerosue

Upgrading the firmware to 4.10.0001 improved the write time for 10000 pts to about 2 minutes using the PNY card.

Good morning aerosue,

We have been reviewing this whole problem with the compact flash memory cards and read / write speeds.

As you can see from this thread the actual card can have a large impact on the access speed but there are a number of other things we are currently working on inside the DT80/800 to help speed things up.

The DT80 uses FAT32 and binary files. The DT800 will do the same with Version 5 firmware latter this year. (No date set at this stage)

Cheers,
Roger