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Hi guys, I have two machines and in both controller boxes I have the AXBB-E, and I really like how they perform. I have been doing some more reading on the charge pump safety circuit port and I know that it is turned off in my current settings and I wonder if it should be turned on. I would like to know if anyone has a more thorough understanding of what this does and if I need to wire a switch to it in order for it to work.

Thanks in advance.

gills wrote:I wonder if it should be turned on. I would like to know if anyone has a more thorough understanding of what this does and if I need to wire a switch to it in order for it to work.

The purpose of the charge pump circuit is to provide a way to disable the axis drivers when the UCCNC (or other) software is inactive. That is, it can be used to prevent the axes from moving until a CNC program is running. Whether you'll need to use a relay with the charge pump circuit will depend on the drivers you have installed and their capability. One example where a relay is used is shown on page 28 of the AXBB-E manual.

I do see that, and I have that pin 17 wired for a laser. But I also read in the manual page 21 section 8 that port 1 output 1 is for the safety charge pump. So is this strictly an internal function of the board or do you have to wire a relay and a manual switch to it? In Mach its listed in the outputs, so do you just activate it there only and do not need a switch? i am running open loop 32 bit dsp drivers.

gills wrote:I do see that, and I have that pin 17 wired for a laser.

I don't understand why you're mentioning pin 17. The charge pump uses O1, and page 28 of the AXBB-E manual shows O1 connected to a relay to disable power to the drivers.

So is this strictly an internal function of the board or do you have to wire a relay and a manual switch to it? In Mach its listed in the outputs, so do you just activate it there only and do not need a switch?

It is an internal function, so no external switch is required to trigger it.

If you're not already using O1 as a simple output, then you would configure the charge pump pins in Mach3 and disable Output 1. The relay on page 28 is used because the example turns off power to the drivers. It's one option for disabling the drivers, but not necessarily the only option.

If you are already using O1 for some other purpose, then you'll have to move that function to a different pin before you can use the charge pump function.

i am running open loop 32 bit dsp drivers.

That doesn't tell us very much.

I would like to know if anyone has a more thorough understanding of what this does and if I need to wire a switch to it in order for it to work.

It's just an output signal that gets activated when UCCNC is running and not in reset.
You can use this signal in a circuit to disable electronics and/or prevent the machine from being powered up when UCCNC (or Mach3) is not running.