PWM outputfrom EMC2

[tottish]

Hi y'all!
I've used EMC2 for my simple 3-axis CNC-router for about a year now so I'm familiar with the AXIS user interface and the StepConf-wizard but other than that I know very little about EMC2.
I'm about to hook up a laser to the machine and here is where I need your help.

1. To start out with I would just like to be able to turn the laser on and off from EMC2 (a TTL-level logic signal or similar would do fine) and I guess that should be simple enough, still I don't have any experience in this area and would much appreciate your opinion on the simplest way to implement this.

2. Eventually I would also like to be able to control the output-effect of the laser which is determined with a 24kHz PWM. Is this possible to get right out of the parallel-port of the PC?

Thanks a lot, hope you can point me in the right direction.

Regards
/Tottish

[chester88]

To turn an output on and off you might use M62 -65.
In stepconf select 'digital out' on one of the parallel port pins
then M62-65 can control it.
read more in the manual.

[tottish]

Thanks a lot Chester! I will check those out in the manual.

Any idea about the PWM thing? I was thinking I might use some output meant for a RPM regulator or something like that. Maybe they are all controlled by analog voltage?

Regards
/Tottish

[chester88]

have you looked at the emc wiki?
In the wiki search laser
for instance here:
http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?M5i20_Laser
This was done using some custom hardware but the principal is the same.
Unfortunately I don't think there are M commands to set analog outputs.
This would be a good feature request.
It could be done using custom g code subroutines to set the pwm generators pulse rate.
look under G100-199