Re: [CAD_CAM_EDM_DRO] Pico VS IMService???

kdntool wrote:

>Hello all,
>I was hesitant to post this question as I do not want any trampled
>toes!
>I am interested in a real world comparison between Pico's universal
>stepper board used with EMC, and IMService's deskCNC w/ thier
>controller card. I am looking from a machine controller aspect ie
>assuming I did not need the "drawing import" functionality of
>deskCNC.I am currently using EMC and a homemade "breakout board".Any
>feedback will be appreciated.
>
>

Well, you may consider me biased, but I'll try to be objective.

First, my Universal Stepper Board performs all the functions of a breakout
board, and then some. It generates very smooth trains of step pulses, and
can do that at very high rates. I demonstrated it at the NAMES show
running Gecko 201 drivers in the x10 microstepping mode, and I was
running up to 90 IPM, where the USC board was delivering 45,000
steps/second per axis. This, of course, is not the limit, it can go to
about 300,000 steps/second.

It also is not limited in step/dir current drive capability, and can source
or sink 12 mA guaranteed on these outputs.

It allows you to connect encoders from the motors to the board, which then
relays the position information back to the CNC computer. One of the
greatest advantages of this is that you can switch back and forth between
CNC and manual operation, and use the computer as a DRO when in
manual. The coordinate system is not disturbed when making this switch,
either. This also can allow the computer to monitor following error, and
report if the motors lag too far behind the commanded position.

The USC board also has 14 opto-isolated inputs for limit and home switches,
so you can have separate indications of - and + limits for each axis.
It also has inputs for emergency stop switches, driver fault sensing, etc.
Also, it has positions on the board to mount up to 8 solid state relays
to control spindle, coolant, etc. Finally, you can use a spare step output
to control a variable-speed drive for the spindle. (There is also an
additional 8-bit port for a spindle DAC that doesn't take up the 4th
step channel. I have not gotten the software to support this feature
just yet, but it is the next piece to tackle.)

Jon