Dear Friends (can you tell I need help?)
I wanted to add homing switches to my mini mill. After looking around I decided on purchasing these Opto Endstops switches;
http://reprap.org/bin/view/Main/OptoEndstop_2_1 from searching the forums this switch seemed like a reasonable choice, a standard 5v source and easy to assemble.
So I assembled the switch and mounted it as shown on the Z axis. Of course I did a bench test and every thing seemed ok. Here is a photo of the Z opto endstop;
http://www.dfurlano.com/optoz.jpgI created a small cover and taped it over the switch (in white) used a cat5 cable and I then connected the switch to a 5v power connector from inside my PC. I checked the voltage and I was getting 5v in and 4.2v out of the switch. When I move the Z up the LED lights and the voltage goes to zero and I thought I was ready to go.
After some consideration I thought I would buy a second parallel port for my PC after searching the forum I found that people had successfully used the SIIG Cyberpro board so I purchased a new one from Newegg and installed it in my PC. I set the address for the SIIG and it again seemed to function properly.
I then mounted all four homing switches and bench tested them. All seemed to work. Then my luck ran out. When I began testing I found first that some LED's were remaining lit after homing. I read that the procedure is to hit the switch and then back off so it does not stay triggered. Well I was getting all confused about what was going on so I started over with just the Z being connected. But it is clear something is wrong not only does the LED remain lit but most times the homing stops short of actually triggering the switch. I checked the voltage and clearly when I am off the switch I read 4.2v and when I am on I read zero. Not sure if 4.2v is not good enough and that is why it is randomly stopping (seems odd that it would work then not work) or do I have another problem?
I somehow need to trouble shoot what is going on. I tried to find a printer port monitor but the only one I can find have preset addresses to monitor the ports and my second port is not one of the presets.
I am lost on what I should try and do and I was hoping that someone could give me a suggestion or offer any advice on how to figure this out.
As always thanks in advance for your help.
Dan