Hi from new member, with VCC risetime question for the SAM7S

On the AT91SAM7S, can the VCC risetime be slower than that of Vcore?
The data sheet implies this, but does not actually state it.

I'm fighting a problem that appears once in a great while, where it appears that the CPU fails to boot.

We've identified VCC rise as an issue, TST tied to GND with 1k (changing that to 0 ohms ASAP).

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>On the AT91SAM7S, can the VCC risetime be slower than that of Vcore?

Datasheet:

"During startup, core supply voltage (VDDCORE) slope must be superior or
equal to 6V/ms."

Atmel FAQ:

Most known SAM7 Boot Problems Question
What are the most known boot problems for SAM7?
Answer
1- VDDCORE slope constraint of 6V/ms. Only for the AT91SAM7S and AT91SAM7X.
Applicable to VDDIN when using the on-chip voltage regulator to power
VDDCORE.

If you're still having problems I'd review checklist:

http://www.atmel.com/dyn/resources/prod_documents/doc6258.pdf

Then contact local FAE, and keep in mind rev. C die release imminent.

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