Homing switches not recognized linuxcnc

Boltonbrass wrote:

I am wondering if my breakout board is working. I did away with the usb cable and hooked up a 5v power supply. The home all button is back

There is almost no chance that hardware changes would make the home-all button appear and disappear.
The button is created by Axis if it can see a home sequence number in the INI for each axis. It pays absolutely no attention to any hardware.

Boltonbrass wrote:

I know the pins are not linked in the hal, but there should be some voltage to the switches.

Not necessarily. Some BoBs have opto-couplers on the inputs. You need to wire them such that current flows through them, which normally means 5V from somewhere on the BoB to one side of the switch then the other side of the switch to the BoB input terminal.

Do you have a link to docs or a web page of the BoB?

Boltonbrass wrote:

Yes I do have docs on the breakout and you see them at omc-stepperonline. .

This one?

It does have optos on the inputs, but they seem to have onboard pull-ups.

You should see the parallel port pin state change in LinuxCNC when you connect any of the input terminals to the bottom common gnd terminal on the left-side terminal block.

Is that how you have the switches wired?

I wouldn't necessarily read too much into the measured voltage on the terminals, but you should have one multimeter probe on the input pin and the other on the common gnd pin at the bottom when testing.

But, what really matters is what HAL sees. The parallel port tester is probably the best tool.

Boltonbrass wrote:

I the switches wired to ground and pin 12 and 15. I would think there would be some kind of voltage to the switches. The hal pin tester will probably help. What about a better breakout board? Pmx 122 maybe?

When you say "GND" do you mean the bottom terminal of the input block or some other GND?

That BoB ought to be as good as any other. They don't have a difficult job to do, the parallel port is the limitation and spending a lot on a BoB can only partially fix that.

I can't see much point paying $80 for a BoB when for $60 you can have (As an example) store.mesanet.com/index.php?route=produc...83_85&product_id=291 which gives you 72 IO lines and hardware step generation. Admittedly you still probably need to spend at least another $45 on breakout for the FPGA board and then feature-creep will step in)

If your existing BoB doesn't seem to be working then you could start poking about the opto-isolators with the multimeter to see what might be wrong, they are pretty simple devices. But bear in mind that they are operated by current, not voltage. The wiring makes a lot more sense when you look at it that way.

Boltonbrass wrote:

I tried to get the latest working ran into problem with it.

What problem did you run into?