PathPilot controlled lathe toolchanger

Hello
I have developed an 8 position toolchanger for my lathe I am using a 5i25 and 7i76. The bit files that come with the 5i25 are set up to produce 5 step and direction channels. I have used a pic micro to decode the pwm signals produced by PathPilot but had to implement a software pwm gen. Is it possible to change one of the step and direction channels to a hardware pwm. Has anyone already done this or could explain how this is done or should I contact Mesa ???

Its possible to change one of the step or dir outputs to be a PWM output instead but would require a custom bit file
(its not a big deal if you have the tools setup. Ive got a stack of custom bitfile requests I will try and get to end of this week or early next week )

sure just let us know what pin arrangment you need
and what current pinfile your using ( sticker on the back of the 5i25 )

Hi Andy
Will have a look at the pins later. PathPilot outputs a pulse width relevant to the tool number I have programmed the following using the capture compare registers on a pic and a timer. Works Perfect.

rise = get_capture(1); // CCP_1 is the time the pulse went high
fall = get_capture(2); // CCP_2 is the time the pulse went low


The times are in Milliseconds for 1ms the range is 900 to 1050 as the PWM gen is software generated it gitters around a bit hence was wondering if I could get a more stable hardware PWM signal.

int tool_found(long new_width){
/// printf("\r\n in Tool found function");
int tool;
if (new_width >= 900 && new_width <= 1050){
tool = 1; }

else if (new_width >= 1900 && new_width <= 2050){
tool = 2; }

else if (new_width >= 2900 && new_width <= 3050){
tool = 3; }

else if (new_width >= 3900 && new_width <= 4050){
tool = 4; }

else if (new_width >= 4900 && new_width <= 5050){
tool = 5; }

else if (new_width >= 5900 && new_width <= 6050){
tool = 6; }

else if (new_width >= 6900 && new_width <= 7050){
tool = 7; }

else if (new_width >= 7900 && new_width <= 8050){
tool = 8; }

else if (new_width >= 8900 && new_width <= 9050){
tool = 0; }
else
tool = 0;

return tool;
}// end func

The 7I76 has lots of I/O
That does seem like a more direct route

That is, you are not working under the same constraints that Tormach
was when they designed their Tool changer interface
(Mach and only one output pin available on parallel port to select tool changer position)

Mike , sent you a pm , their are other ways to do this , but depends on if your using a tormach bit file
i can easily add a toolchanger into pathpilot easier probably than your trying to do ..

Sarah

Thanks CNCBASHER the bit file works fantastic the pwm signal is rock solid have done some testing and all is great. Glad I could help with the setup of PathPilot have put a picture of the toolchanger mounted on George's myford lathe.

Thanks

Micknucam

micknucam wrote:

Hello
I have developed an 8 position toolchanger for my lathe I am using a 5i25 and 7i76. The bit files that come with the 5i25 are set up to produce 5 step and direction channels. I have used a pic micro to decode the pwm signals produced by PathPilot but had to implement a software pwm gen. Is it possible to change one of the step and direction channels to a hardware pwm. Has anyone already done this or could explain how this is done or should I contact Mesa ???

Micknucam may I ask what PIC you used in your tool changer. I was able to get a Emco PC Turn 50 tool turret and will convert it for use on the NovaTurn. Your method seems to be straight forward. Can you share your code?


Thanks,

Iron-Man