Is it possible to contorl Drivers with analog inputs?

Hi all. We have old CNC machine and it's software is very old. I would like to change controlling software. I use linuxCNC as basic for stepper motors.

But in this old CNC machine is used Servomotor drivers with analog inputs.
Does it possible to control them with linuxCNC?
If Yes, then what methodology I should use?
I heared about LinuxCNC EtherCAT, if it possible to connect I/O modules to LinuxCNC how to convert impulse output to analog?

For controlling old analog servos one of the simplest hardware options is a Mesa 5i25/7i77 combination.

But before you commit to that hardware, you should confirm what kind(s) of feedback your system uses. The 7i77 needs to have feedback from incremental (quadrature) encoders.

Thanks Todd for your answer. Encoders is easy to setup.
How Can I configure analog output of speed instead of pulse?

The Mesa cards handle the digital to analog conversion, and the 7i77 card connects directly to the analog controls of the drive. Setting up Linuxcnc to do it is easiestly done using the PNCconf wizard for configuring Mesa hardware. Think of it as Stepconfig for Mesa hardware.

The basic overly simplified description of how it works is Linuxcnc sends a position command to a PID loop (Hal PID component). The PID recieves that commanded position and compares it to the feedback position from the encoders, and then uses that info to to generate a velocity command that becomes the analog signal to the drive. This all happens very very fast (updated once/servo thread cycle), and in a well tuned system, can keep the following error within just a few encoder counts.

Thanks to all guys, that give me vector to move. I've found such nice topic with your help.

www.gnipsel.com/linuxcnc/configs/7i77.html