Breakout Board Speed Control

Hi,

I currently am trying to control my spindle's speed using my BoB's analog output pin. It provides a max of 0-10 V out. I want to use this signal to control my KBIC speed controller, but it requires an analog voltage that is between 0 and 7 V. I'm not sure as to how to go about doing this. I've looked at the documentation but am still confused. I just want to test to see if it is actually working, so if someone could just slap together a HAL file that is able to do this so that I can test it, I would be really appreciative. I want my spindle to go at a maximum speed of 1400 RPM, and on my BoB the analog out is pin 1.

Thanks,
Logan

Be careful as many KBIC speed controllers have a analog speed control
input that connect directly to line power, so requires an isolated analog
voltage source.

I believe my BoB is optically isolated ( this is the link to it ). I just would like an example HAL file with my settings. When I measure with my multimeter after using stepconf, I get nothing even after I issue a command like s500 (my axes have all been zeroed). 

I tend to think I'm making some sort of mistake. I currently am only making use of the PWM pin, do I also need to include pins for turning my spindle on and off as well?

Logthor wrote:

I believe my BoB is optically isolated ( this is the link to it). 
 

I just measured it. The 5V and 12-24V voltages are isolated from each other, but 12-24V is also used to power the home, estop and probe inputs on the opposite side of the board. If there is a risk of applying high potential to the 12-24V power supply, it is safer to use a separate cheap Chinese PWM->0-10V board and a separate small power supply. As for the 0-7V range, it is probably enough to scale the spindle speed appropriately (for example, setp pwmgen.0.scale 2000 instead of 1400, i.e. 1400 rpm will be 70% of 10V)

I tend to think it'll be fine as all I'm using the 24V is for my homing switches and powering the board to let me control the spindle.

Regarding how I go about controlling the spindle, I'm not sure about how to do it. I have attached my hal file below. When I measure the voltage between the pins circled in red I get 0.01 Volts (even after I've homed my axes and and sent it an m3 s500).