[j-nsp] Sandisk Extreme III 1G CF card compatibility

[Dave Diller]

>> It turns out that some SanDisk Extreme III 1G cards are Juniper
>> friendly, and others are not.  We purchased three at the same time
>> from the same CompUSA.  Of the three, two do not work and the third
>> one is fine. The symptom is that the non-functional ones time out and
>> you can't install anything on them (but 6509's are fine with them, so
>> they'll be redeployed there ;-):
>
> I believe the distinction is that some (usually modern high-speed  
> units,
> or especially cheap regular units) CF cards do not support PIO mode,  
> and
> assume that anyone in their right mind buying a 1G CF is going to  
> plug it
> into a device which supports UDMA, and high speed UDMA at that.

True in general but not in this specific case; the Extreme IIIs have  
always supported PIO modes 0 - 6 and older date-coded ones work fine  
with both RE-4.0 and Sup720.  Newer ones don't work with RE-4.0 but  
are still fine in Sup720.  Something changed internally and makes  
Juniper puke, even though the card is labelled the same.  Different  
chip?  Clocking tolerances?  Donno.

> You're best off getting a regular classic SanDisk with PIO support,  
> there are no
> benefits to be had by putting nice CFs into old and crappy hosts. '

Agreed, the hardware certainly isn't going to be able to make use of  
the faster card.  The main benefit to the "nice" 1G Extreme IIIs has  
been ready availability at any walk-in store and low price.  But that  
seems to no longer be the case unless you find old stock.

But, OTOH, "standard" 1G Sandisk [SDCFB-1024-A10] is $18.95 on Amazon.  
That's just nuts.  Especially since they sell the 512M version for  
$32.95 ;-)

-dd