Lpc2000

Hi John

If the datasheet specifies what your saying then there's not need for
opions as it's a bad design or simply a mistake brought about (let me
give you a practical example) 

We have a secretary where I work and she doesn't know a resistor from a
transistor but she looks damn well good and does the accounting...

One day as she was doing the "shopping" at Arrow (I believe it was) 

She was instructed to purchase the 74ACT244 (or what ever the 3.0V type
is called) but she found that she could get the 74??244 which in the
sales catalogue said "Super fast rama dama ding dong" and she thought
that it was better :o) The thing is we purchased a shit load of these
which we couldn't use and even though I'd like to punish her the dirty
way I don't think it would help... 

Well back to the issue at hand :) 

Maybe the same thing happened to Olimex? 
I "know" that at least Tsvetan which I "know of" is a descend man and
knows what he's doing so It could well be a slip up I will recommend you
to exchange the dongle to Olimex or replace the IC your self 

Regards
Lasse


-----Original Message-----
From: johnnorgaard2003 [mailto:john_2005@...] 
Sent: 20. oktober 2004 15:32
To: lpc2000@yahoogroups.com
Subject: [lpc2000] Olimex ARM JTAG Signals levels



Hi Olimex/Others

I have an Olimex ARM JTAG. It works ok on my homemade board if Vcc is
3.3 V. But if Vcc is 3.1 V is does not work.

I have look at the JTAG.
The board contain a 74AC244 (5V driver - power from PC)
The board contain a 74LCX244 (3.xV driver - power from target)

Signals from Target through 74LCX244 OK, but from 74LCX244 to 74AC244,
do not work 3.x volt to 5 volt system.

I think the 74AC244 should be replaced by a 74ACT244 ???

What is your opinion ?


Best regards
John Noergaard






 
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