On 1/13/2012 7:57 AM, andy pugh wrote: > I had an idea of a way to measure analogue voltages with EMC2 a few days ago. > > It ought to be possible for a HAL module to send a sawtooth PWM signal > on an output pin, and monitor one or more input pins. Externally a > PWM-voltage conversion circuit and a bank of comparators would switch > the input pins when the variable pwm-generated voltage was greater > than the voltage to be measured. > > This is a fairly normal analogue voltage measurement technique, but > puts the cleverness inside HAL, where EMC2 can see it. > > Sampling period would probably be several mS, but that is probably OK > for many uses. > >
That sounds like a lot of work. If you aren't concerned about speed, a modbus link to a cheap PLC is hard to beat dollar wise. Or what about using an Arduino for Analog I/O? Dave ------------------------------------------------------------------------------ RSA(R) Conference 2012 Mar 27 - Feb 2 Save $400 by Jan. 27 Register now! http://p.sf.net/sfu/rsa-sfdev2dev2 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
