-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Somebody in the thread at some point said: | Andy Green wrote: |> How did you determine that it is "undriven"? It's pulled up somewhere, |> right? What does the rise and fall times look like? | | Here's a transition from apparently undriven (~1V) to low: | http://people.openmoko.org/werner/dat1-falling.png
1V sounds evil, I don't think we should ever see that static level on 3.3V SDIO interface. We have 10K pullup on D1... R7906, so "undriven" means it has pulldown of ~8K to 0V to reach 1V? Truly undriven would surely mean it was 3.3V via the pullup. Maybe try to reduce the pullup. | By the way, do you know what rise/fall time is actually allowed ? | Whenever it comes to this kind of interesting detauls, the SDIO | spec only cheerfully proclaims "This section is not included in | the Simplified Specification." :-( No, the reason I asked was because I wondered if too high a pullup resistance was allowing the interrupt to look asserted at the start of its slot depending on the data level when it stopped driving, it would need to be > 1us to make trouble I guess. - -Andy -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Using GnuPG with Fedora - http://enigmail.mozdev.org iEYEARECAAYFAkkgeO4ACgkQOjLpvpq7dMrADwCfYLhfSmkEQbfkTJYteVG2zDUg uoQAn188TfyNNBj73XXBMIQneBLJB8Bd =9t6O -----END PGP SIGNATURE-----
