BOB ZP5A-INT and input troubles

Hi.
By now it's about 2 months I'm fighting with the input side of my BOB ZP5A.
The output side works fine (the 3 motors run like piece of cake - sorry if it's a wrong figure of speech, I'm from Italy...), but no way to make the limit switches working.

I asked even the italian community to help me, but nothing to do.

Making some tries with the configuration, I get an error message "Contact on limit 0" (sorry I'm translating from the italian version of LinuxCNC) or no response at all.

There's no way to make the inputs working (I tested the pins 10 - X limit - and/or 15 - ESTOP)

I asked to a collegue in my office (he manages our systems), and his opinion is that something has to be configured somewhere in Linux to tell the software that parport works as in/out, and not only as out.

Honestly, I don't know what to check more.

I tried to use the BOB with 2 PCs (a laptop IBM and a desktop), getting the same results.
I tried also buying a second BOB (a generic chinese one), maybe the problem is the BOB, but even this new one gives me the same problem.

Till now, the only "solutions" i can find is to use the BOB only as is it now, and build an external device to ensure the safety of the machine, i.e. arduino connected to limit switches and driving a relay wich cut off the motors power line. But this way, I can't have a self-zeroing/homing machine, nor stop the job dinamically (meaning I will lose the entire cnc job), but at least I can save the hardware

Searching on the web, I found a lot of people having trouble like mine, but I couldn't find any useful infos for my problem, or when someone update the post with "SOLVED", there's no useful indication about how the problem has been fixed......

I attach my HAL file and the configuration (the laptop).
I hope some of you can help me to fix it.

Thanks in advance

Andrea

This sounds like a wiring problem. Start by telling/showing us how you've connected things to the bob?

What kind of switches are you trying to connect to your inputs?

I believe that bob requires an external 5v power source (from a USB connection or other). Do you have that connected?

IF you have shared home and limit switches, you need to make sure there is a HOME_OFFSET to move the axis off the limit switch when homing. Otherwise, if the home/limit switch is left enabled, as the machine comes out of homing, it sees and reacts to the limit switch error and faults.

Todd wrote:

This sounds like a wiring problem. Start by telling/showing us how you've connected things to the bob?

What kind of switches are you trying to connect to your inputs?

I believe that bob requires an external 5v power source (from a USB connection or other). Do you have that connected?

Attached there's my BOB (you don't see any pwr led 'cause the system was off).
The 5V are provided by the PC USB, but I tried even with a wall PSU - 1Ah I think it's more then enough: same issue
The parport cable use a gender changer, but I got even a new cable: same issue (all cable's pins checked as working)
The limit switch is wired to P10; the 2 wires on P15 should be the Estop (it was a quick test...)

I asked for support even Zapp Automation (where I got the BOB); they told me I need just a simple switch (as is it....), but they cannot help me 'cause they work only with Mach3 and no LinuxCNC....

rodw wrote:

IF you have shared home and limit switches, you need to make sure there is a HOME_OFFSET to move the axis off the limit switch when homing. Otherwise, if the home/limit switch is left enabled, as the machine comes out of homing, it sees and reacts to the limit switch error and faults.

Honestly right now I don't remember... (last time I worked on it was las saturday....) when I back home from office I'll check; but I'm pretty sure by now I'm working setting only the Limit, to avoid any mistake

Lets start at the beginning. Have you tried opening Linuxcnc and watching all of your parallel port's input pins with Hal Meters or the watch screen in Hal Configuration while you toggled one of the inputs with a switch?



Do that and take note of which connector toggles which parport hal pin. (Maybe the input pins are not connected to the parallel port pins you think they are.)

Then make the appropriate changes to your config.

I tried even this check, but I got no life signs in HAL Watch for those pins....
I'm waiting for a PCI parport to check even if maybe the problem is the onboard parport (the laptop is an IBM Thinkpad and the desktop is Asus P5A MB based)

This is the BOB I've used. This is about £6 from Banggood or other Chinese suppliers. It needs 12v for the inputs to work. It might be worth getting one just to check.

Have you checked what your parallel port settings are in your bios? SPP mode is probably most likely to work, but try all of them.

raglanlittlejohn wrote:

This is the BOB I've used. This is about £6 from Banggood or other Chinese suppliers. It needs 12v for the inputs to work. It might be worth getting one just to check.

I got 2 of them (one from amazon and one from china - still waiting for the one from china).
I'll check it during the weekend, see what happens....

Todd wrote:

Have you checked what your parallel port settings are in your bios? SPP mode is probably most likely to work, but try all of them.

My parport bios setting is EPP (reading here and there, I found EPP should be the right setting, but it's most possibly I misunderstood, so tonight I'll try by changing it to SPP - or the others too)

Last night I did several tries....
1) Installed and external PCI parport (NetMos based) with 2 more partport (but only the one onboard, I didn't plug the wired one by now). In the bios I found a second (?) parport address (278) now. By listing in debian (lspci -v) I found 6 new addresses (see attachment). By editing my HAL file manually adding the second port with the address B800 (the first in the list), in the hal monitor I can see the second parport. I connected the BOB on the second directly but no change (honestly, I'm pretty sure I made something wrong...)
2) disabled in the bios the onboard parport, using only the pci. Same issue.
3) enabling again the onboard one, now the bios report me even a 3 (?) address 3BC (now the list is 378H,278H,3BCH....)

Then I gave up, as my soulmate was staring me with no honey in the eyes (I don't know if it sounds good in english, but "the honey in the eyes" in italian means "plenty of love").

Optimistically, I hope it's only a software issue (even if it drives my crazy...)....

Andrea

Well....
It's all working......
The solution was as raglanlittlejohn suggested: wire both power inputs

The chinese one worked very fine.

Then I tried with my ZP5A, by wiring both the power inputs, and it finally works fine.

What make me p***ed off is that on both BOB's user manuals there's nothing about that....

ZP5 manual reports the BOB as working OR via USB power OR via external power (switching the selector on the board).

None of both of them report something like "Note, if you want to use the inputs you MUST connect BOTH power inputs"....

By the way....

Thank all of you for your patience and support.

Andrea