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Larry;


If I look at the ATA Spec "SRISE" in the table of AC characteristics is
1.25V/ns for the rise time for less than UDMA Mode 4. It also states that
its for "any signal". I deem this to include RESET. Fall Time is not
mentioned, but is it really needed. Also the RESET is defined as a Totem
Pole attached signal. I also now the the RESET is not a edge level triggered
signal. 

When we increase the UDMA mode above 4 the Rise Time changes and the Fall
Time is now included, but this is for only for DD(0-15) and STROBE.

Note 1 is mentioned in each case. I leave that to the reader.

I conclude that the ATA specification, could be clearer and specific is all
applicable data transfer modes for all signals.

Thanks
Tom Colligan




> From: Larry Barras <[EMAIL PROTECTED]>
> Date: Thu, 12 Dec 2002 14:12:44 -0800
> To: [EMAIL PROTECTED]
> Subject: [t13] Rise time of HRESET de-assert?
> 
> This message is from the T13 list server.
> 
> 
> In reading the spec, I have a question regarding the rise time of the
> ATA Hard Reset line. What is it? There's a specified minimum hold
> time of 25 �s, but nothing regarding the rise and fall times of the
> signal.
> -- 
> 
> ---------------------
> I make stuff go.
> ---------------------
> 
> Larry Barras
> Apple Computer Inc.
> 1 Infinite Loop
> MS:  306-2TC
> Cupertino, CA  95014
> (408) 974-3220

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