Seeing as Compact Flash uses a standard IDE interface, would it be possible to attach an ordinary hard drive to a camera via a compact flash slot? There are many adaptors on the market that go the other way (allowing you to use compact flash cards as hard drives in a PC), but I haven't seen anyone attempt this yet, except with microdrives. Is this possible?
It depends on how the camera implements the CF slot, but the answer is almost certainly not, for two reasons:
The CF storage cards can be operated in any of three modes; memory-mapped, IO or True-IDE (which is the IDE emulation mode used by those adapters). Cameras tend to use memory-mapped mode because True-IDE mode does not support hotplugging.
Even if the camera does use True-IDE mode, it probably uses the
8-bit subset of this mode. CF cards are required per spec to support
8-bit data transfers. Only a VERY VERY FEW old IDE hard disks (designed for compatibility with PC/XT computers) support this mode. Any modern drive will only support 16-bit transfers. Also, there is no way the camera will be able to power a hard drive.
Abe Cd wrote: : Seeing as Compact Flash uses a standard IDE interface, would it be : possible to attach an ordinary hard drive to a camera via a compact : flash slot? : There are many adaptors on the market that go the other way (allowing : you to use compact flash cards as hard drives in a PC), but I haven't : seen anyone attempt this yet, except with microdrives. : Is this possible?
It is _probably_ impossible, period. But this depends on how much work you're willing to do and how much information you already have. It is _certainly_ not worth the effort :)
The camera will most likely not implement the extra 8 data lines to the slot. So you would need to find some way of "creating" 8 extra GPIOs and wiring them to the slot connector. That's a given, since in order to talk to a hard drive you MUST have the full 16-bit bus.
If the camera uses IO mode, it may have run the signals driving the CF slot to hardware that generates the correct timings and select signals. It might not be possible to change that even by changing the firmware. You'd have to evaluate this on a case-by-case basis.
You'll also need mains power or a separate battery to power the hard drive, since the tracks to the CF slot will not be rated for the couple of amps a hard drive might require.
And of course, all this assumes that you have full access to the datasheets and firmware source for the camera. If you also have to reverse-engineer the chip and its software, then ....... This is not a feasible project.
Won't work in this application. The CF slot on those SBCs is a very special case. It is simply the secondary IDE channel from the super I/O chip, routed to a CF slot instead of a 40-pin IDE header. Since they already have the full 16-bit bus "for free", they implement all 16 lines on the CF slot.
That passive adapter won't work on any device that only implements an
8-bit data bus, nor will it work on any device that uses a slot mode other than True-IDE.