Re: [CAD_CAM_EDM_DRO] making DRO boards (was Re: Card, kit or schematic for Kuluga/Mauch DRO card

alex wrote:

>>I've designed hardware for ISA bus, and PCI bus. PCI is much more
>>
>>
>involved
>
>
>>in more ways that I should list in this email.
>>
>>One way to get a head start would be to find a PCI prototype card with
>>something like an AMCC 5933 or PLX 8??? PCI interface chip already
>>attached. From there, the voltage and time sensitive signals will already
>>have been handled.
>>
>>There could still be a lot of work required to get the PCI configuration
>>registers set up properly, and the right information programmed into the
>>serial EEPROM that often hold the power-on configuration.
>>
>>I'd be tempted to build some logic that sat behind a parallel port, and
>>then use a PCI parallel port card. You could put the encoder interface
>>into a small FPGA.
>>
>>

I've already done this. I have a card with an FPGA that connects to an
IEEE-1284 parallel port,
and reads 4 encoders. It has options to read differential encoders, and
can use an index channel
for several functions, like resetting the count to zero for a spindle,
or just flagging that the index
pulse has been seen. This card was designed to be used with a DAC and
digital I/O card for a
servo system, but could be used by itself.

I have another card that handles everything for a 4-axis stepper system,
with the option of encoder
feedback. It has 4 digital step rate generators that can produce step
pulses with 100 nS timing
resolution. it can generate step pulses and accept encoder counts at
over 300,000 counts or steps
per second. It also has 16 opto-isolated digital inputs and place for 8
solid state relays to plug in
directly, avoiding the need for a separate Opto-22 IO mounting board.

See http://pico-systems.com/PPMC.html for more info. Most of that page
describes the first
board set above, but a link at the bottom for the Universal Stepper
Controller takes you to the
description of the all-in-one stepper board.

Jon