Probe Connections - General Electronics - Arduino Forum

Probe connections Other Hardware General Electronics johnboy1 June 24, 2021, 4:21pm 1

Hi All,

Which pins are used on a cnc shield when used with a Uno that will allow me to connect a probe for my CNC machine that I am building. Is there a diagram available? or any other info I should know.

I intend to install a 6mm jack plug socket on my control box connected to the shield.

Thanks in advance guys.

chrisknightley June 24, 2021, 4:50pm 2

We need accurate information about the shield you are using. Did the vendor provide the schematic?

The "CNC shield" has a standard schematic... But there are several versions and the configuration is different.

groundFungus June 24, 2021, 5:22pm 3

Are you using a controller firmware like grbl or Marlin?

johnboy1 June 24, 2021, 5:25pm 4

Hi, I am using GRBL

johnboy1 June 24, 2021, 5:27pm 5

Hi , unsure about the make, it came from China with the UNO, it’s red if that’s any help?

groundFungus June 24, 2021, 5:31pm 6

like this?

For grbl the probe connects to the SCL (A5) pin and ground.

chrisknightley June 25, 2021, 2:18am 7 johnboy1:

it came from China with the UNO, it’s red if that’s any help?

If it matches what @groundFungus posted, do so.

The cheap clone CNC shield purchased from China is probably "CNC shield Ver 3.0". Currently, I think that many originals are V3.1 and V3.51, but very cheap Chinese clones are old one.

TomGeorge June 25, 2021, 2:57am 8

Hi,

johnboy1:

a probe for my CNC machine that I am building.

What probe? Can you please post a link to spec/data for the "probe"?

Thanks.. Tom..

johnboy1 June 25, 2021, 6:41am 9

That’s the one, so A5 and ground pins are the pins to use. Will it require any further electronics between pins? Thanks

groundFungus June 25, 2021, 8:54am 10

Google "grbl probe" for lots of information.

system Closed October 23, 2021, 8:55am 11

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