🚀 go-pugleaf

vinoski@ch.apollo.hp.com (Stephen Vinoski) writes:

>This is fine for chip test, but for board test it would better if
>there were only one controller for all the chips on the board.  See

A good time for me to clarify our present test philosophy...

Actually, that is what we hope to accomplish.  By placing a Micro-
processor and one Test Bus Controller with multiple scan path linkers
on the board, we can apply stimuli vectors, saved in an EPROM, to the 
"boundary" of one functional block of the board, then observe the 
response by collecting the resultant vector on other scan paths in 
other functional blocks.  

This "embedded test" will be used for connectivity testing between 
ASIC's where the number of functional ASIC stimuli vectors would be 
too high to apply in a timely fashion after power-up and before the 
system ready state.

In case folks where wondering, yes there are plenty of non-scan parts
on this board that I also have to write tests for.  That's the part 
I've done before.  And yes we will have approximately 6K scanable ASIC 
pins, plus some scanable registers and fifo's on the board as others 
have questioned. Sounds exciting I know!

My final goal with the embedded test at power-up is only to achive a 
level of funtionality confidence, and not complete ASIC functionality.  
Thus the 1149.1 architecture features that we install will contain the 
"hooks" to perform more thorough testing on the manufacturing floor using
a non-resident test processor in a PC for instance, as a diagnostic tool
in module test or burn-in.  Prior to this step, the ASIC's will have been
tested at the foundary before pc board assembly and at the ATE station 
after pc board assembly.

>In a previous life I wrote a lot of scan software.  I found that the
>use of object-oriented software development techniques greatly reduces
>the chances for errors while allowing relatively powerful tools to be
>developed quickly and reused for different applications.

Others have mentioned the Object Oriented approach as a wise choice.
Thank you for the advice and the references.

Actually!, Thank you all for the many responses.  Between all the phone 
calls with new vendor product leads, and all the new reading material,
a a couple of well deserved vacation days, I've not had enough time to
respond to everyone.  

Let's keep this discussion going.  I still have a ton of questions...

Ed Kearns
BBNASD
Bellevue,Washington