I thought I would pass on some recent experimental information about using the dual counter +5V as the voltage source for the channel counting.
I an using a TEMP08 (with 200mA power supply) on a single daisy chain 1Wire network about 100' long constructed with CAT5 cable. The network has 2 1WIO cards and a single Dual Counter card located at the end of the 100' daisy chain. The TEMP08 is tied into a HomeSeer Hometroller 2. The dual counter was connected to a breadboard application circuit via a 4N25 opto-isolator; the counter card +5V was tied to one side of the 4N25 detector and Channel B input to the other side.
The dual counter card appeared to be 'seeing' excess counts associated with household electrical noise events like the furnace circulating pump stating and stopping or the oil burner starting and stopping. I initially assumed this to be caused by the application circuit I was working on and made a number of modifications to its +5V and +12V power supplies; these had no effect on the false counts.
After much incremental testing I performed the following test; I tied the counter card +5V directly to the Channel B input completely eliminating my application circuit; since the counting occurs on high to low transition, the channel should never count. However, when the furnace start/stopped the false counts continued to be generated (also whenever I use the electric pencil sharpener).
I then externally powered the dual counter with a battery pack and performed the same test as above; the false counting stopped. Since the application circuit has a +5V power supply, I am now externally powering the counter card by connecting the application circuit GND to the dual counter ground and the +5V to the dual counter +5V. I was initially concerned that the addition of another ground would compromise the 1Wire communications but this does not appear to be the case.
Bottom line, the dual counter is no longer reporting false counts during household electrical noise events.
Best Regards,
Mark
I an using a TEMP08 (with 200mA power supply) on a single daisy chain 1Wire network about 100' long constructed with CAT5 cable. The network has 2 1WIO cards and a single Dual Counter card located at the end of the 100' daisy chain. The TEMP08 is tied into a HomeSeer Hometroller 2. The dual counter was connected to a breadboard application circuit via a 4N25 opto-isolator; the counter card +5V was tied to one side of the 4N25 detector and Channel B input to the other side.
The dual counter card appeared to be 'seeing' excess counts associated with household electrical noise events like the furnace circulating pump stating and stopping or the oil burner starting and stopping. I initially assumed this to be caused by the application circuit I was working on and made a number of modifications to its +5V and +12V power supplies; these had no effect on the false counts.
After much incremental testing I performed the following test; I tied the counter card +5V directly to the Channel B input completely eliminating my application circuit; since the counting occurs on high to low transition, the channel should never count. However, when the furnace start/stopped the false counts continued to be generated (also whenever I use the electric pencil sharpener).
I then externally powered the dual counter with a battery pack and performed the same test as above; the false counting stopped. Since the application circuit has a +5V power supply, I am now externally powering the counter card by connecting the application circuit GND to the dual counter ground and the +5V to the dual counter +5V. I was initially concerned that the addition of another ground would compromise the 1Wire communications but this does not appear to be the case.
Bottom line, the dual counter is no longer reporting false counts during household electrical noise events.
Best Regards,
Mark