[hpsdr] What can we do with 2 cards

[Eric Ellison]

Phil et.al

Just an offhanded thought based on my previous.

If you were to add an Aux Power connector to the OZY to source the board
directly could it become a stand alone FPGA development system? AKA Xylo? If
I got the 'drift' right in the flurry of messages yesterday and before, The
program loading is going to be via the Ozy so if it is powered locally it
shouldn't need the Buss. Also the header for the 20 GPIO could be used for
'stand alone' experimenters (as well as all the other proposed connections).

In theory I it should be possible to plug an Ozy and Janus end to end
without Atlas. Dyslexia can't let me figgre it out.

Still too early and not enough coffee or sleep here. Just thinking out loud.

Eric


-----Original Message-----
From: hpsdr-bounces at hpsdr.org [mailto:hpsdr-bounces at hpsdr.org] On Behalf Of
Philip Covington
Sent: Saturday, May 13, 2006 7:57 AM
To: Bill Tracey
Cc: HPSDR List
Subject: Re: [hpsdr] What can we do with 2 cards

***** High Performance Software Defined Radio Discussion List *****

Hi Bill,

If we agree to forgo the Logic Analyzer/Debug Port(s) and also agree
that we will never expect to add external SRAM then I can drop the I2C
IO stuff and provide somewhere around 32 I/O off the OZY.  I think you
can do all 3 below then.  Then we need to discuss how to
protect/buffer those lines in a way to allow all 32 to be inputs,
outputs, or a combination of both.

I am leaving soon this morning, and on the drive to/from home I will
be thinking more about this.

73 de Phil N8VB


On 5/13/06, Bill Tracey <bill at ewjt.com> wrote:
> ***** High Performance Software Defined Radio Discussion List *****
>
> When we started down this path with the Xylo I think one of the
> configuration goals we had was:
>
>          1. Sound Card replacement
>          2. Ultra Low Latency CW input
>          3 .SDR 1000 Parallel Port Control
>
> As we morphed to HPSDR my hope was that this configuration could be done
> with two cards - Audio (Janus) and USB/FPGA (Ozy)
>
> At the moment it looks like we may only be able to do #1 with 2 cards.  We
> might be able to do #1 & #2 if we can get low latency CW keying via I2C
I/O
> via FX2.    We certainly cannot do #3 with just 2 cards.  At the moment on
> the Xylo prototypes we've got PTT/DOT and DASH coming thru FPGA pins and
> their state gets integrated into the audio data stream going to the radio,
> giving very low latency..  Doing CW via I2C via FX2 may have sufficiently
> low latency, not sure of this.  I'd assume we'd have to read from an FX2
> USB endpoint to get the status of the ports -- anyone know if one can do a
> blocking read waiting for the state of the I2C ports to change from the PC
> -- hate the idea of having to poll the USB port at a hi rate for good CW
> performance.       I don't think we can do SDR 1000 parallel port control
> with the I2C expander as it takes 17 (D0-7, C0-3, S3-S7)  lines, also not
> clear to me  how quickly we can and need to wiggle those lines to program
> the DDS in the SDR 1000 when going via an I2C.
>
> One idea to get back to doing dot/dash directly thru the FPGA is to go
> through the Janus.  It looks like there are 4 unused I/O on the Janus
> CPLD.  Could we add some protection circuitry on the Janus to 2 of those
> lines and configure the CPLD to put those sigs on the Atlas bus.   Maybe
> add 3 more pins to the 0.100 unbalanced audio connector?
>
> I that's not  viable, is there space for protection circuitry for 2 lines
> on the Ozy  and a 3 pin connector?  Could we jumper the configuration of
> the FPGA serial port such that it's either tied to the level converter or
> the external connector?
>
> Just some late night thoughts -- trying to find a way to get a little more
> function into a 2 board setup.
>
> Regards,
>
> Bill (kd5tfd)
>
>
>
>
> _______________________________________________
> HPSDR Discussion List
> To post msg: hpsdr at hpsdr.org
> Subscription help: http://lists.hpsdr.org/listinfo.cgi/hpsdr-hpsdr.org
> HPSDR web page: http://hpsdr.org
> Archives: http://lists.hpsdr.org/pipermail/hpsdr-hpsdr.org/
>
_______________________________________________
HPSDR Discussion List
To post msg: hpsdr at hpsdr.org
Subscription help: http://lists.hpsdr.org/listinfo.cgi/hpsdr-hpsdr.org
HPSDR web page: http://hpsdr.org
Archives: http://lists.hpsdr.org/pipermail/hpsdr-hpsdr.org/


 1147523212.0