I only had about 10 minutes last night to work on the Mendel but I came away happy. I had figured out that my firmware was probably not correct for my boards so I downloaded a new version specifically for the techzone hardware. I loaded it up on both the main board and the extruder and got some great results.
All 3 axis are now working, although the Z axis seems to be intermittent. Sometimes it doesn't move when I jog it and the stepper makes a squealing sound as if it is jammed or something. A couple of times it moved just fine though so I think that this is probably a hardware issue (something stuck in the gears etc.). I will take a look at it tonight. The correct commands are definitely getting to the steppers now though.
Also, the hot end of the extruder is heating up just fine and the thermistor is passing good data back to the board. I was using Pronterface last night and could easily track the temp as it went up.
I didn't have any filament in the machine but I hit "extrude 5 mm" a couple of times to see if the extruder stepper would rotate. It didn't move so that is my biggest concern at the moment. I set the desired temp to 0 and it still wouldn't move so I guess it is not something in the firmware as I had suspected. I may have the stepper wired incorrectly but I didn't have time to check last night.
This will be a long weekend here in Canada for Thanksgiving and it is supposed to rain all weekend. That means that I should have lots of time to work the bugs out and get something extruded. I also have to move our entire home office down to the basement so my wife can have the spare room to set up an office for her new accounting business but what the heck, I have three whole days!