DataFlash Datasheet question

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#1
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In an effort to sound dumb, I have to ask what should be an obvious question.

On page 10 of the AT45DB081B datasheet table 1 list 10 different opcodes for various read commands. If we just take one as an example:

"Buffer 1 Read" has two possible Opcodes 0x54 and 0xD4

0x54 is for "Inactive Clock Polarity Low or High"
and
0xD4 is for "SPI Mode 0 or 3"

From the Atmega128 datasheet page 169 it would appear that "Inactive Clock Polarity Low" is in fact SPI Mode 0!!!
Similarly "Inactive Clock Polarity High" is in fact SPI Mode 3!!!

So what am I missing? Please be gentle. I know it's something obvious.

Shannon

Go electric!
Happy electric car owner / builder

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Total votes: 0

...bump....

either my question was TOO dumb or it's a stumper....

Go electric!
Happy electric car owner / builder

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Total votes: 0

After further investigation it looks like "Inactive Clock Polarity High" and SPI Mode 3 are identical. The evidence is a comparison of page 25 and page 21 of the AT45DB081B datasheet. "Inactive Clock Polarity Low" and SPI Mode 0 are not identical OR there is an error between pages 23 and 19. Since it's clear I'm the only person who cares :lol: I'm going to have to go with SPI Mode 3 and then try both Opcodes D4 and 54 to see if there is a difference!

This will leave me in one of two states:

Both Opcodes work. The conclusion will have to be that the datasheet has a LOT of extra information about two modes that don't exist!
The Opcodes are different: The conclusion will have to be an error on either page 25 or 21.

Either way it looks like a confirmed error in the datasheet!

Go electric!
Happy electric car owner / builder