I'm using a Tech Arts Micro Core system and am interfacing three CDS cells and three GP2-D120s. The 68HC11 has two banks of four A/D channels and all testing on my wiring indicates that there are no shorts or open circuits. My software can read analog voltages from both sets of ports.
Here's what's happening: If I have one of the GP2-D120 units plugged in to any of the three ports, it works fine on any port. I also checked each unit and each works fine.
If I have more than one GP2-D120 plugged in, the 68HC11 board starts resetting itself constantly. I had the inputs floating and tied high with the same results. (except that the no-sensor values was different)
I entertained the idea that maybe they were drawing too much current, but they are listed as a continuous draw of about 33 ma. I have the electronics buss powered with a 1800 ma NiH battery pack. I'm feeding off of the Micro Core regulator. But I doubt that's doing anything because I also have serial LCD that draws well over 100ma when the LED backlight is on. I have it shut off now, so, the total should be less than 160ma for everything on that regulator.
Is there some special magic to get these units to work together?
Thanks in advance, Joe Nastasi