I have 3 motors managed by a Chinese 4-axis board.

https://fr.aliexpress.com/item/32918200137.html?spm=a2g0o.productlist.main.15.31927a38hHL5zY&algo_pvid=2070012e-b8cf-4db4-b7dc-f20f27ffc20a&algo_exp_id=2070012e-b8cf-4db4-b7dc-f20f27ffc20a-7&pdp_npi=4%40dis%21EUR%216.61%216.59%21%21%216.72%216.70%21%40210390b817354862584254867e4333%2110000012811635421%21sea%21FR%211897906811%21X&curPageLogUid=hchAF7XenEek&utparam-url=scene%3Asearch%7Cquery_from%3A

Finding the right wiring diagram was particularly difficult.
The 3 engines run well with Mach3.
The only thing I notice is that, with identical adjustment parameters, the 3 motors run slower on x than on the other 3 axes: I wonder why ...
I would like to add 2 axes. Buying a Chinese FIVE-axis board will probably lead to the initial result : major cabling problems.
So I'm considering buying the same 4-axis "white eagle" board.
My question is: is it possible to run 2 occurrences of the program simultaneously ?

My question is: is it possible to run 2 occurrences of the program simultaneously ?

No, that would not be possible.

Tweakie.

If I buy a new interface board from China, I'm afraid I'll have big wiring problems.
I think I'm going to stick with my 4-axis board and place several inverter switches to manage, from time to time, the fifth axis

Another possibility: not to add inverters but to keep the current setup for XYZ and to add another Windows (which I have) for the toggle and rotation of my divider. I then have my 5 axes but I have to buy a second manual steering wheel.

What is the best ?

What do you mean by inverter?

interruptor with 2 states
first item of https://www.manomano.fr/pieces-detachees-pour-petit-electromenager-4725?model_id=67237821&referer_id=697152&msclkid=9258a352f4be19ba2269c42692620acf&utm_source=bing&utm_medium=cpc&utm_campaign=Bing%20Shopping_CPC_FR_B2B&utm_term=4575892537250586&utm_content=Tous%20les%20produits

Change-over switch

It would help if you could explain what you want to accomplish. Is it just to add a rotary axis? Why does that need 2 axes, what's the difference between toggle and rotation? 

https://fr.aliexpress.com/item/1005006353184440.html?spm=a2g0o.productlist.main.3.5d4dxCw7xCw7KM&algo_pvid=1f6f3413-9014-4a38-a3e6-dac442f48d6f&algo_exp_id=1f6f3413-9014-4a38-a3e6-dac442f48d6f-1&pdp_npi=4%40dis%21EUR%21207.47%21200.69%21%21%211542.53%211492.12%21%40210384cc17357478264454986ea5e7%2112000036863166808%21sea%21FR%211897906811%21X&curPageLogUid=3bC97Yaf8iBu&utparam-url=scene%3Asearch%7Cquery_from%3A

In France, this is called a divisor ... On this device that I will use FROM TIME TO TIME, 2 movements are possible: the rotation of the workpiece, the tilting of the support (mandrel or vice or flanges) of the workpiece. I want to make these 2 movements FROM TIME TO TIME thanks to 2 Nema34 8.5 Nm motors. For the tilting, I ordered a helical gear (which will bring an inaccuracy...). For the rocker, I ordered a ball screw with a diameter of 25 mm.

Modify does not work.   Strange

For the tilting, not the rocker