Lpc2000

> If you have a web site of what your doing here, I would like to see
> some pics.

Hey Don,

I work for Caltech's Owens Valley Radio Observatory (OVRO).
We've recently combined with the Berkeley-Illonois-Maryland
Array (BIMA); Caltech had 6 10m radio telescopes, BIMA had
9 6m telescopes. You can check out the observatory's web page

http://www.mmarray.org

(click on the Telescopes link on the RHS)
or Caltech's web page

http://www.ovro.caltech.edu

Or my stuff

http://www.ovro.caltech.edu/~dwh/correlator

The correlator is the digital backend to the telescope and
is what I primarily work on. There is a documentation
link on the left hand side, and check out the 'SZA wideband'
correlator link.

I've been playing with ARM devices since I received a
development kit from Circuit Cellar for their Philips 2005
design contest earlier this year.

The telescopes have historically used two types of encoders;
parallel NPL encoders, and serial BEI encoders (I've no idea
what the letters mean). The microVAX systems in the antennas
will be replaced, but not now.

The SZA array is an array of 8 3.5m telescopes. They use
a Heidenhain 27-bit encoder (and do NOT use microVAXs, so
no conversions required there). The side-job I have picked up
is to create an adapter board for the OVRO antennas, that
converts the 27-bit Heidenhain output to either the 21-bit
BEI or NPL interface so that dead (and irrepairable) encoders
can be replaced with Heidenhain, with the microVAX being
none-the-wiser.

(The encoder is a Heidenhain RCN827 and it uses the EnDat
serial protocol, www.heidenhain.com).

I've got a PCI DIO24 board (Computer Measurements digital
I/O board) hooked up to an encoder, so I know how to read
the 27-bit encoder using its serial protocol. When I get the
BEI and NPL interface information from another engineer
here at work (after Thankgiving sometime), I'll know what
I need to emulate to interface to the microVAX.

I can implement the adapter purely in an FPGA, but at some
point the microVAX will be retired and I'll want to talk
to the encoder over CAN. A lot of new equipment here has
been designed using the Philips XAC 16-bit micros and
uses CAN. I'd like to design using the LPC devices.

I'll post any results when I get them.

Enjoy!
Dave