[Elecraft] KPA500/K3 AUX bus specification

[ANDY DURBIN]

"fraught with danger"?


It's hard for me to imagine how monitoring an "output only" bus with a DSO could be "fraught with danger".   There would be nothing connected to the AUX bus except the DSO and a pull up resistor.   About the only way I can see to cause any damage is to exceed Io max of the 2N7002K.


What risks have I overlooked?  I don't want to void the warranty while there are still unresolved issues with my KPA500.


73,

Andy k3wyc


________________________________
From: Don Wilhelm <donwilh at embarqmail.com>
Sent: Sunday, April 29, 2018 5:42 PM
To: ANDY DURBIN; elecraft at mailman.qth.net
Subject: Re: [Elecraft] KPA500/K3 AUX bus specification

Andy,

While you seem capable of reverse engineering the AUXBUS, it is fraught
with danger if you get it wrong.
You are "own your own" in this matter.

73,
Don W3FPR

On 4/29/2018 7:37 PM, ANDY DURBIN wrote:
>
> Don,
>
>
> Thanks for the reply.
>
>
> I'm familiar with the PC interface and have, in the hope of tracking
> down a problem, built a logger that uses that bus to interrogate the
> KPA500 at 10 Hz.  I was hoping the AUX bus would give a faster
> detection of a spurious band change than my 10 Hz interrogation ^bn;.
>  I'll look at the bus with my DSO but I have already been given
> information than suggests its data rate will be too low to be useful.
>
>
> I may have to resort to instrumenting the shift register signals from
> the front panel to the LPF but I was hoping to avoid that.
>
>
> 73,
>
> Andy
>
>
>
>
>
> ------------------------------------------------------------------------
> *From:* Don Wilhelm <donwilh at embarqmail.com>
> *Sent:* Sunday, April 29, 2018 2:45 PM
> *To:* ANDY DURBIN; elecraft at mailman.qth.net
> *Subject:* Re: [Elecraft] KPA500/K3 AUX bus specification
> The AUXBUS protocol is Elecraft proprietary and is not published.
> It is the single wire communications between the K3 and its options,
> both internal and external.
>
> The K3 Programmers Reference and KPA500 Programmers Reference gives you
> commands that can be issued from a PC or other connected computer -
> those commands are quite extensive and can give you complete control
> from a PC.
>
> 73,
> Don W3FPR
>
>
> > From: elecraft-bounces at mailman.qth.net
> [elecraft-bounces at mailman.qth.net] on behalf of ANDY DURBIN
> [a.durbin at msn.com]
> > Sent: Sunday, April 29, 2018 3:59 PM
> > To: elecraft at mailman.qth.net
> > Subject: [Elecraft] KPA500/K3 AUX bus specification
> >
> > Can someone please point me to a definition or specification for the
> KPA500 - K3 AUX Bus.   I have the KPA500 Programmer's Reference but
> this appears to only cover the KPA500 - PC interface.