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HP 50g & SD Cards: Performance, Format, Notes
07-22-2016, 12:06 AM (This post was last modified: 07-22-2016 12:21 AM by JDW.)
Post: #30
RE: HP 50g & SD Cards: Performance, Format, Notes
(07-21-2016 12:57 PM)Claudio L. Wrote:  What becomes slower with cluster quantity is ON time, the time between pressing the ON key and getting the stack ready to work. This is because during ON, the card free space is calculated, and it needs to read the entire FAT table for that. More clusters means larger table. Also FAT32 tables are twice the size of FAT16 tables with the same number of clusters. Joe didn't measure ON time unfortunately...

Joe subsequently replied it takes "less than a second" (900ms?) to turn ON with all cards but FAT32. Let's ignore FAT32 and focus on all those other FAT16 cards that take 900ms for the Calc to turn on. I would assume that more than one of those cards has >2MB/s speed ratings. If so, how then does one explain the speed differences Joe posted?

That is my main area of interest. I fully realize the calc is limited to 2MB/s. But if we assume that more than one of Joe's cards has a 10MB/s or even greater rating, how then do we explain the speed differences in Joe's test?

Furthermore, if Joe gets a calc turn ON time of 900ms or so, how much faster is the turn ON time for those of you who use smaller <256MB cards?

Joe, I found out that the fastest card in your test is rated at 10MB/s (p/n: INX-SD1GCN):

And the 2nd fastest SD card in your test, the Pretec 60x, has a speed rating of 9MB/s.

The 3rd fastest card in your test was the PNY 2GB formatted FAT16, which is rated at 4MB/s:

The 4th fastest is noticeably slower than the top 3, and is the PNY 512MB. I Googled and Googled but cannot find a speed rating. Check the card's model number and Google it to find the rating. If that card's rating is 2MB/s or higher, then I would like to know why it would be noticeably slower than the first 3, seeing the calc is limited to 2MB/s.

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RE: HP 50g & SD Cards: Performance, Format, Notes - JDW - 07-22-2016 12:06 AM

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