Lpc2000

----- Original Message ----- 
From: "Stephen Pelc" <stephen@...>
To: <lpc2000@yahoogroups.com>
Sent: Tuesday, January 17, 2006 10:55 AM
Subject: [lpc2000] Building DIY wiggler w/74VHC08


>> From: "Leon Heller" <leon.heller@...>
> 
>> I think that is probably the case, contrary to what I said
>> earlier. Ground bounce due to poor construction techniques may be
>> one reason why some people have problems getting it to work
>> reliably.
> 
> Some PC printer ports generate fast (<10ns) spikes of up to 1 
> volt amplitude on some pins. They can be very difficult to 
> remove, and will often trigger buffers that have TTL threshold 
> levels. Most printer ports now run at about 3v and if the device 
> is powered through the printer port, it is probably operating 
> way outside its datasheet specs.

Mine is powered by the target system.


Leon