Hi,
I am new to CNC machining so please pardon my naive questions.
I want to control a 20,000 ppr ac servo motor which came with its driver using a PC.
However, the parallel port motion controllers provide very low frequency step/direction signals (~25 KHz) which gets me to about 1 rps or 60 rpm.
the motor is capable of doing 3000 rpm.
So, my question is how to generate a very high pulse rate ie about 1Mhz to 3Mhz (like the propriety controllers). I realize that the propriety controllers use dedicated hardware to generate such high pulse rate and communicate with the PC over the PCI bus.
However, my intuition (supported by calculations) tells me that it should be possible to convey position data to a hardware board using USB and then use the dedicated microcontroller to generate step and direction signal.
I have designed PC to USB device communications int he past using PIC 18f4550 and Atmel ARM AT91SAM7 series as well as Atmel AVR32 UC3A and AP7000 processors. So I can definitely design the communication of position data (1 ms intervals) of the various axes as well as I/O sampling over USB to the microcontroller.
However, I am drawing a blank when it comes to the generation of high speed step/direction signals.
Any ideas on this?
Regards,
amit