I think the addition of two parameters to the M571 command would be really helpful for pneumatic based systems.
Most pneumatic systems suffer from a lag between the time the gpio pin associated with the M571 pin goes high and the time extrusion begins. This is generally due to mechanical compliance in the hardware.
If a parameter could be added that sets the output high in advance of a move with extrusion (usually less than 500 milliseconds)) it would account for the time it takes the system to reach adequate pressure. Similarly, if the pin could be driven low before the move with extrusion ends, it would help prevent ooze during de-pressurization.
Right now I am managing it with a "extra prime amount" when slicing in Cura, but It is problematic because it only works after a retraction.
Pressure advance as currently structured does not meet the need because it only functions during the extrude command, not in advance of it.
Thanks

Thanks. That seems to work.
I guess I was concerned that I would't be able to re-connect unless I had a USB connection, but I see that I can just use M552 S1 at the console on the PanelDue.
Thanks for helping with what should have been obvious to me. I'm not used to this hardware.

I would like to set up my machine in a "demo" mode, where I can print files already on the SD card in an environment where I dont have a wireless network.

Currently, the popup error messages associated with not having a wireless connection keep showing on the PanelDue 5i and they obstruct the other menu buttons making it impossible to select files from the SD card.
Is there a way to disable the error messages so they don't keep popping up?

My Hardware setup is: Duet2 Wifi 1.04C + Duex5 and PanelDue 5i
FW: RRF3

Thank you for getting this to me.
On a related note, my application uses my two duet extruders for other axes.
I don't actually need an extruder per se. However I do need to use the M571 to open and close a valve.
Do I need to attach a Duex5 so that I can define an extruder to reference? I currently do not have one attached, but I have one available.
I tried defining all 9 drives in my config.g [...M569 P5 S1], Mapping it to drive 5 [M584 E5] as well as setting up a Tools that use the extruder, but I get a tool definition error if I try to use an extruder other than D0 or D1 in my M563 command. [M563 P0 D2 S"Color 1" F0 ].

Will I be able to use the M571 to drive a fan output (F2), or only GPIO pins? I am driving a solenoid during extrude commands.
Currently I am using external circuitry (mosfet) activated by GPIO, so activating a fan output directly to drive the solenoid would save some circuitry.

Thank you for getting back to me so quickly! I'll give it a try.

I am driving a relay via a mosfet triggered on logical pin P1 which I setup using:
M950 P1 C"exp.9" ; create GPIO pin 1 on pin 9 of expansion connector
M42 P1 S0 ; set GPIO port 1 to Low

I intend on using the M571 command to open a solenoid valve during extrude moves

An M42 P1 S1 activates the solenoid, but for some reason If I enter a command:
M571 P1 S1 I get an error stating "M571 P1 S1 Missing port name string".

Running RRF3 on a Duet2 Wifi Rev 1.04c.

Does anyone have any experience with this?
Thanks.

I am trying to use a fan [fan1] output to drive a relay input.
However, even if I use a M106 P1 S0 command, the voltage drops only to 0.4 volts, which is not low enough to switch the relay off. Any thoughts on how to pull the fan output closer to 0V?

@DIY-O-Sphere
Thank You So Much! That works perfectly.
I had no Idea that they added all of this functionality to the M574. It will be really helpful when I switch over to dual Z endstops too.

Here is the config.g file

09Jan2020_config.g