CNC plotter 1800 x 80cm, first build, questions and queries.

[borntofight00]

So far so good!

I'm going to largely ignore your voltage measurements - because I don't understand quite what you've written...

Bad wording, sorry. Anyway, you are correct.

1) My first question is - has you witnessed the actual computer that you're using with Mach3 successfully drive this board? ..

No, unfortunately I wasn't able to see everything working. I was given two PC's during system collection with the information that one of them was used with this equipment and should still be ok.

2) Are you using a full 25w wired parallel cable between the computer and the BoB?..

I'm using brand new 25w parallel cable and I tested each pin for continuity, all fine.

3) Of interest - on the BoB - there's a 3-pin jumper header labelled "JP1" - there should be a shorting pin connecting two of the pins together - which two?

This shorting pin is connecting pins 2 & 3 (COM=GND)

4) Would you be confident to ***CAREFULLY*** measure the voltage on pin-1 of the 25-W D-type that the computer plugs into, with the system powered. I'm talking about connecting the meter black lead to 0V and carefully probing the PCB where the pin-3 is, and measuring the voltage with the X-Axis moved in one direction, then again with the X-Axis moved in the opposite direction. In one direction you're expecting a voltage less than perhaps 0.8V and in the other direction greater than perhaps 2.5V.

I managed to measure a voltage for X, Y and Z axis (just in case) and I was getting just a little bit above 2.5V and 0.07V (not too low?)

5) Much easier - could you do this again on the PC. insert a couple of pins or bits of stripped solid strand wire (paperclip?) into pin 3 and pin 25 of the PC parallel port and measure for each direction of X-axis travel. If you can provide a photo of this for our amusement (and validation) - this is getting to the point where we should be able to understand the PC->BoB communication - I think the BoB's basically functional, so this is important to understand why the BoB is not seeing the commands from the PC.

Take a look at the pictures attached, for your amusement :) I’m measuring 3.35V & 0.036V, almost identical on pins 3 to 9.

From what I understand, there is a communication between PC and BOB, but there is no signal to the outputs .. as you can see at the picture, BOB is a little bit messy so would it be a good idea to give it a good clean with isopropanol for example?

Another thing that I have spotted is LED next to PC power terminals which was illuminating for some time while PC was running but the rest of the system wasn’t powered. At some point, it disappeared .. is it normal?

I really appreciate the time you spend pointing me in the right direction.