there's 10v running between the "estop input" and "input ground"
I'm building my first cnc (wood router) and I can't get any of the inputs to work.
I've got the demo version of mach3 and I can move x,y & z and even cut a few shapes but I can't get the estop and other inputs to work,
when I hit the estop it's like the signal isn't getting to the pc, the mach3 diagnostic page shows no change and the autoset on the input options isn't detecting it either.
I've tried setting the input to pin10.
I've tried changing the parallel port mode to epp, ecp and even a ps/2 and at modes but it's still not working.
it's windows xp 32bit on a dell optiplex 780
There's 10v running between the "estop input" and "input ground"
The only weird thing is that the "Relay" LED goes off when the pc boots up.
I've attached a pic of my wiring, any help would be great.
Thanks
Pete
Similar Threads:
Last edited by ppeettee; 06-14-2016 at 09:18 AM. Reason: Additional information added
there's 10v running between the "estop input" and "input ground"
You seem to have or had the same problem that I am currently having. My assumption was that the BOB was defective(same as yours) so I got another but the problem still existed. No e-stop or limit switch verification in MACH3 diagnostics by manual activation of the limit switch. I don't see any posts as to what the solution if any might have been. Any information concerning this issue would be very helpful, Thanks
Check the voltage across the optocoupler's output. See if that voltage changes as you operate the e-stop button.
I have not seen that particular breakout board, but it does appear to be using an optocoupler. Some people will run a higher voltage through the e-stop switches like 12V and interface that to a relay or an optocoupler to address noise concerns. The other side of the optocoupler should be configured to either drive high or drive low. Does the output of the optocoupler change when you mess with the E-stop switch. Also keep in mind depending on your board it might make the output High or Low depending on how it is wired. Many parallel ports on PCs have the inputs pulled high, so the opto would need to be configured to pull the E-stop pin low. You can test the parallel input port for pin 10 by pulling it to ground without the Breakout board attached and see if MACH3 changes on the diagnostics page.
Russ
looking at the online photos of the breakout board
the two 74HC245 IC's that buffer the 12 printerport outputs are powered by +5V from a USB port
the PWM circuit and the five "817C" optoisolated inputs (Estop & L/S 1-4)
are powered by the "317" regulator that drops the +12 to 24V down to +10V
as far as I can see the Collectors of the NPN photo transistors in the 5 input optoisolators are connected to the printerport inputs (pins 10 to 13 + 15) without any pull up resistors on the B.O.B
this may be a problem when used with printerports with a weak internal pullup
( for P10 you can easily see the Collector connection going to the 25pin connector)
the photo transistor emitters being connected to the printerport ground
John
This circuit diagram that John-100 posted expects to see LOW inputs to the optocoupler, and it also expects the parallel port input pins to be pulled up which is pretty common on most parallel ports. The transistors in the OPTO pull P10 to P15 low when activated. This means in MACH3 you have to make sure your INPUTS on these pins are ACTIVE LOW.
Russ
Why is no one questioning the E stop switch/circuit.....? The switch is supposed to interrupt the circuit. Looks to me as he has ground to one side and low voltage in on other.... I think the E stop should break the connection of those 2 pins right? Looks like he's not completing the circuit...
Samsung Note 7.5
for now the main thing is to get Mach3 to respond to any of the inputs
once that problem is solved ,
the next decision can be made
is a software only E-stop is good enough when using a single pole N/C E-stop switch
or an independant E-stop circuit that kills the power to the machine and flags the E-stop the the motion controller / PC
for now Pete can check the change in voltage levels at the input optoisolators collector (pin4)
if the voltage changes are valid
0 to +0.7V for a logic 0 and more than +3.5V for a logic 1
if the inputs are valid the next thing is to double check the mach3 setup
has all the changes made been saved ?
E-stop = pin10
John
Last edited by john-100; 11-11-2016 at 04:43 PM. Reason: edit typo
5v
I'm sure you have figured this out by now but I wanted to post because I was running into the same problem with a board that has 3 relays on it.
On the board I'm using there is 5v power out at P10. I was connecting to P10 as if it was a typical input. Instead of grounding P10 directly to ground, I ran one end of the e-stop circuit to P10 and the other end of the e-stop circuit to GRND in the same bank of connectors on the BOB.
At first I was running 5v power through the e-stop circuit to P10 and essentially feeding 5v at each other.
I suggest testing the board (with a voltmeter P10 to GRND) and see if P10 has power High as default. If so, run P10 to GRND through the e-stop circuit.