Re: parallel port not working with emc?

Can EMC redefine the assignments of pins 14,16,17?

The current pin assignments are as Irby indicated for both the
stepperworld FET-3 board 14,16,17 as x,y and z enables) and for EMC
(using Freqmod according to the EMC manual 14, 16,17 are unfortunately
assigned to B step, C dir, C step repsectively).

I wrote to Rustle Laidman of stepperworld and he explained:

> The (FET-3) axis enable bits are active LO, however pins
> 14 and 17 are inverted in (the parallel port) hardware,
> so in software you would set them HI.
> Another way to think of this is to SET 14,17 HI, and 16 LO to
> activate all axis.

Dan

PS. Rustle also verified that the parallel port assignment address is
independent of the operating system (not an obvious fact for a
newbie). So I can stop suffering over the confusion about 378h
(hexidecimal) and 0378 or 0x378 (decimal?).

> I think the problem may be that EMC doesn't use any pins for enable,
> and the FET-3 needs pins 14, 16, and 17 set high (or maybe low) to
> enable the steppers.
>
> I am running an older version of EMC, so I don't know if the pin
> assignments are changed from it to the version of EMC you are using.
> If the pin assignments are the same as my version, and from what I
> can find about the Stepperworld FET-3 driver, here are the pin
> assignments ("step" is the same as "clock"):
> EMC FET-3
> pin 2 X direction X direction
> pin 3 X step X step
> pin 4 Y direction Y direction
> pin 5 Y step Y step
> pin 6 Z direction Z direction
> pin 7 Z step Z step
> pin 10 spare Z home switch
> pin 12 X/Y/Z home Y home switch
> pin 13 X/Y/Z -limit X home switch
> pin 14 B step X enable
> pin 16 C direction Y enable
> pin 17 C step Z enable
>
> If this is the problem, you need a way to set pins 14, 16, and 17
> high (or low, if that's what's required) all the time. There are a
> lot of ways to accomplish this, but without knowing exactly what you
> have, I can't offer anything specific. The first thing that comes to
> mind would be an interface cable that has pins 14, 16, and 17 wires
> to something that is at +5 volts all the time. If that doesn't work,
> try connecting them to ground.
>
> Hope this helps.
> Irby
>

my original post

I have installed the Feb 2005 version of EMC and everything seems fine
except that the motors do not spin. My controller worked with an
older version of emc but I have moved and had to start over.

I can run a gcode file such as the sample file "cds.ngc" and view the
(hypothetical) output on tkemc's (view > backplot ). The "backplot"
shows the moves and "io_show" shows the parallel port pins, in charge
of direction, toggling. EMC will run all the way through to the end
of the sample file. So I think the install is ok.

I have a dual boot set up so I was able to test the exact same
hardware via a windows program that came with the stepper driver (a
stepperworld FET-3 driver and the program vbstepdirxp). The windows
program will spin the motors so I know that (at least in windows using
vbstepdirxp) the hardware path all the way to the motors is ok.

I suffered for a time over the IO port designation within EMC. In
windows the correct port name is 378h but looking under the system in
tkemc I find two "parport0" addresses 0378-037a and 0778-077a so I'm
using the designation 0x378.

I tried to test the output voltage at the end of the parallel cable
with a hand held voltmeter but the results are confusing at best.

So I am wondering what I am doing wrong. Any help would be appreciated.