Contradictory or confusing documentation about Watchdog

Moderators: TomKerekes, dynomotion

Post Reply
RogerFroud
Posts: 78
Joined: Tue Mar 30, 2021 8:07 am

Contradictory or confusing documentation about Watchdog

Post by RogerFroud » Mon May 03, 2021 7:20 pm

I'm trying to get my head around what this is all about, and find the documentation baffling.

On this page...

https://dynomotion.com/Help/SchematicsK ... analog.htm

... this comment "One Enable or Watchdog FET Switch Output is also available (24V @ 1Amp). This switch conducts after Kflop boots, enables the +/-15V generator, and begins communicating with the board."...

presumably refers to JP8.9 where it's labelled as SwitchEnableAll? Why not use the same wording to avoid confusion? What is the comment " (24V @ 1Amp)" supposed to mean? It looks like the FETs are all connected to ground, but this comment could be interpreted as implying that it's supplying 24V, else why mention 24V? Again, I presume it actually means that 24V is the maximum permitted voltage that the FET can sink to ground.

Looking at this page...

https://www.dynomotion.com/wiki/index.p ... dware_Info

... it appears that yet another name is being given to JP8.9, this time SWE? Is this the same? If so, why not label these pins the same and actually include the connector and pin numbers so there's no confusion?

Doubtless this is blindingly obvious when you're familiar with these boards, but coming to it for the first time it's not clear.

So, after going round in circles for a while, it looks like JP8.9 will sink a load to ground up to a maximum of 24V and current of 1Amp, becoming active when KFLOP and KANALOG are booted and stable. Is that what the documentation is trying to say?

User avatar
TomKerekes
Posts: 1598
Joined: Mon Dec 04, 2017 1:49 am

Re: Contradictory or confusing documentation about Watchdog

Post by TomKerekes » Mon May 03, 2021 8:54 pm

One Enable or Watchdog FET Switch Output is also available (24V @ 1Amp). This switch conducts after Kflop boots, enables the +/-15V generator, and begins communicating with the board."...

presumably refers to JP8.9 where it's labelled as SwitchEnableAll?
correct

What is the comment " (24V @ 1Amp)" supposed to mean?
It is capable of switching up to 24V at up to 1 Amp of current
It looks like the FETs are all connected to ground, but this comment could be interpreted as implying that it's supplying 24V, else why mention 24V?
Because it is limited to switching 24V
... it appears that yet another name is being given to JP8.9, this time SWE? Is this the same? If so, why not label these pins the same and actually include the connector and pin numbers so there's no confusion?
SWE is short for Switch EnableAll and is how the Kanalog pin is marked.
it looks like JP8.9 will sink a load to ground up to a maximum of 24V and current of 1Amp, becoming active when KFLOP and KANALOG are booted and stable
correct
Regards,

Tom Kerekes
Dynomotion, Inc.

RogerFroud
Posts: 78
Joined: Tue Mar 30, 2021 8:07 am

Re: Contradictory or confusing documentation about Watchdog

Post by RogerFroud » Wed May 05, 2021 8:07 am

Many thanks for clearing that up.

Post Reply