Question New to me 840

I recently purchased a 840 black edition and I’ve got some questions. I have a 500w spindle, power supply and motor driver from a different machine that I’d like to use. I’m having some difficulty with figuring out the wiring from the driver to the controller. The driver is a WS55-220S 24v-60v. I’ve got a pin out diagram for the db15 plug on the machine, but just can’t get it to work right. I can get the spindle to turn on through UCCNC but I can’t control the rpm. Any advice would be appreciated. Thanks.