modding IDE cable to write-protect compact flash?

From: Joshua Kuo (josh_at_prioritynetworks.net)
Date: 08/22/03 

Date: Thu, 21 Aug 2003 22:25:12 GMT

hi all:

I am involved in a mini-project that is to build a solid state computer
(mini-ITX based) that will feature read-only medium. we have chosen
compact flash for its relatively cheap cost and larger compacity. and due
to the phyiscal limitations of the setup, we cannot use the popular
USB-flash sticks that come with a write-protect switch, we have to stick
with a CompactFlash-to-IDE converter.

it would be really nice if we could somehow protect the data on the
Compact Flash on a physical layer. we have thought about mounting the
Compact Flash read-only, but that doesn't protect the data on the Compact
Flash to be modified if someone gained super-user access to this machine.

i am wondering if it is feasible to short a few pins in the standard IDE
cable, so that the write signal does not get passed onto the Compact Flash
card. has anyone attempted similar solutions? i would really appreciate
any pointers and suggestions.

Thanks in advance.