Where to start?

The Integrators manual contains the info needed for one to configure EMC while you build or convert your machine. The Users manual contains the info needed to use EMC once you have a running machine. None of my machines use the parallel port...

A servo driven machine needs two "connections" to EMC, an input from EMC telling it how fast to go and the feedback to EMC about it's current position.

A common and easy to connect to is servo drives with 10vdc +- velocity inputs and encoder position feedback. I used a Mesa 5i20 + 7i33TA + 7i37TA to convert my lathe from Siemens control to EMC.

gandalf69 wrote:

I have a Bridgeport Interact 1 that has a slightly defective Heidenhain controller. The XYZ servos and spindle motor and controller work OK. After reading a bit about EMC2 capabilities, I thought it might be interesting to see if it would control the BP with minor mods such as digital encoders.

There are several of those around that have been convered to EMC2. I was under the impression that they used stepper motors, but it sounds like yours has Servos?

All Interacts had servos AFAIK.

I threw a new PC together and loaded the Live CD (10.04 + 2.4.6) and Ubuntu runs OK and the EMC2 configuration selector starts up OK.

I have no idea what to do next.

You could start by looking at one of the servo configs, but see later:

BTW, parallel ports are almost extinct these days. Does this spell the end for EMC?

EMC2 supports other interfaces, and I am not sure that it is a good idea to try to run a servo machine from the p-port. It can be done, but isn't optimal in any other way but cheapness.

Pico Systems do a range of motion control hardware which uses the P-Port as a communications interface, rather than as an IO device, moving voltage generation and encoder/resolver tracking into hardware:
pico-systems.com/motion.html

Mesa (www.mesanet.com) also do a similar parallel port board, the 7i43. That too handles step generation, PWM, direct motion control and a host of other options via downloadable firmwares. At $80 it is very cost-effective and has 48 pins configurable as inputs, outputs or specific functions.

Along the same lines, there are devices from Motenc (OK) and the Pluto-P (just don't)

Moving away from the parallel port there are a number of PCI card solutions. Very popular are the Mesa 5i20 and 5i23. These are basically the same as the 7i43, but with more IO ports.
Other PCI solutions include the Opto22.

Other stuff: wiki.linuxcnc.org/emcinfo.pl?EMC2_Supported_Hardware

The first thing to do is to work out what sort of motors you have (brushed? Brushless?), what type of feedback it has (Hall, encoder, resolver, tachometer?), and how much of the existing setup it is sensible to retain.

Thanks, I'll check out those interfaces. and the Supported h/w.

The servos are brushed, tacho, resolver? (counts per rev), the controller needs to count in order to calculate position.
Personally I think that retaining much of the old robust and reliable servos and drive electronics is a good idea, in the lower price range only the computing hardware and software has improved over the last 20 years IMHO.