[Test-Equipment] Write Protect Compact Flash Cards

[Robert Rolf]

Funny how every post I've ever tried to make to Test Equipment bounces.
But when I'm being unnecessarily flipant, it goes through. My apologies
for the attitude. I'd just finished dealing with a really lazy
dweeb on one of my mailing lists and was fed up with people who
don't seem to RTFM.

Looking further, I see where -WE is not used in 'true IDE mode'
so that won't work for you. 

http://www.toshiba.com/taec/components/ApplNote/TSB_CF-Motorola_PPC8260_030325.pdf
� Card Memory Mode (uses WE#, OE# to access memory locations)
� PC Card I/O Mode (uses IOWR#, IORD# to access I/O locations)
� True IDE Mode (uses IOWR#, IORD# to access I/O locations)

There does not appear to be a way to electrically prevent writes.

Robert Rolf wrote:
> 
> The obvious way. Don't connect to -WE (pin 36) which you pull high.
> There is also a WP pin if the card is used in memory mode rather than IDE.
> 
> Robert
> 
> Rainer Alpert wrote:
> >
> > I'm building a small data collection computer with a CF card in IDE mode
> > as boot device.
> > How can I electrically prevent any writes to the card?
> >
> > Thanks,
> > Rainer Alpert (KC5VHO)