Possibly the device is not held in reset until the power is
stable. I had a 332 design that every now and then would do
strange things on powerup / powerdown since I did not have a
low voltage reset unsing something like the MC34064. Also
since the CF has this built in, be certain every device with
a reset line is connected to it.
>-----Original Message-----
>From: Paul Whitfield [mailto:paulw omnitronics.com.au]
>Sent: Thursday, April 13, 2006 07:48 AM
>To: mikeavantisys.com
>Subject: Re: [ColdFire] 5282 booting
>
>Daniel Weiss wrote:
>> Hi list members
>>
>> I have a 5282 design with the program in external
flash.
>>
>> Problem is I have to power the circuit twice in
sequence in order that the
>> CPU boots properly. Just one time powerup makes it
stuck somehow.
>>
>> Once it runs and I do a hardware reset, it does not
boot again immediately,
>> I have to wait about 20..30 seconds until it starts
booting. During that
>> period it just seems to do nothing. No external
memory accesses. If I press
>> the reset key once more within that 20..30 second
period, it starts booting
>> immediately. Drives me crazy. Has anybody an idea
what that could be?
>>
>
>We once had a similar problem because we had a device on
the
>data bus that was coming out of reset too slow. This
device
>was corrupting the initial program counter and stack
pointer during
>the reset.
>
>Perhaps you can confirm those first transfers are
working correctly.
>
>Regards
>
>Paul
>
>========================================================
=================
>The information in this e-mail is intended for the
addressee only.
>Unauthorised use, copying, disclosure or distribution by
anyone else
>is prohibited. Please let us know immediately if you
receive this
>e-mail in error. Thank you.
>========================================================
=================
>
>--------------------------------------------------------
------------
>To Subscribe send a message to: ColdFire-OnLists.Wildrice.com
>To Unsubscribe send a message to: ColdFire-OffLists.Wildrice.com
>For further information, visit: <http://www.Wild
Rice.com/ColdFire/>
>
>
------------------------------------------------------------
--------
To Subscribe send a message to: ColdFire-OnLists.Wildrice.com
To Unsubscribe send a message to: ColdFire-OffLists.Wildrice.com
For further information, visit: <http://www.Wild
Rice.com/ColdFire/>
|