Simpler than HAL?

[Thomas Watts]

I am interested in stripping down the design of HAL to a simpler, cheaper
form, possibly
using soundcard and just the amps, or by removing the processor stage, and
running the ADC directly off the parallel port. I have done some work on a
possible new layout, using standard generic radio shack PCBs. I welcome
hearing either here or directly from anyone interested in
pursuit of such a goal.
Tom Watts
brainwav93@hotmail.com

[Dave Tweed]

Thomas Watts wrote:

I am interested in stripping down the design of HAL to a simpler, cheaper
form, possibly using soundcard and just the amps, or by removing the
processor stage, and running the ADC directly off the parallel port.

Don't forget about the safety issues -- primarily galvanic isolation from
the AC power mains. This is why the original HAL is battery-operated and
has an optoisolated interface to the PC. When you have deliberately created
low-resistance electrical connections to a living person, even tiny leakage
currents can be lethal.

-- Dave Tweed