I have a Cooler Master ACPI 64-bit 3.2 GHz PC with Windows 7 Professional, and Version 4.9.9.2 of Dev-C++ from BloodshedSoftware. I also have a Fireface UC Win which I would like to use to excite a drive coil at a range of frequencies from the Hz level to 30 kHz or so. Near the drive coil is a metal object, in which current is induced. This current then induces a signal in a nearby search coil. At each frequency, I want to digitise the amplitude and phase of the resulting signal. This will be weak: perhaps 10-100 ppm of the driving signal.

The point of all this is that different metal objects respond in characteristic ways to different frequencies, in a way that depends on their shape (ring, disc, hollow cylinder, etc.) Using this effect, it should be possible to recognise metal shapes in the ground. The application is an improved metal detector, with which to find landmines and other "explosive remnants of war" (EROW) like cluster bombs. You probably know that deminers spend most of their time checking out harmless pieces of metal such as coins, spent bullets, etc. Some way of recognising these objects could therefore be very useful.

My immediate problem is that I don't see how to program C++ to get the Fireface to generate the desired frequencies. Nor do I see how to get the Fireface to analyse the signal in the search coil. OTOH I am able to use a C++ function called Beep to generate sounds, but only via the ATI system that came with the PC, not via the Fireface.

Can anyone help?