Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > sci.electronics.design > #454447

Re: Identification of modules

Show all headers | View raw

On 3/31/2017 2:39 AM, Piotr Wyderski wrote:
> Don Y wrote:
>
>> So, you're planning on discarding the EEPROM in the DS2438?
>
> Yes, not going to use it at all.
>
>> (Make sure the configuration isn't implemented in EEPROM if you mistrust it!)
>
> The problem is not in EEPROM, but the lack of power
> supply/communitation in the case of spare modules.
> The powered ones can be automatically reprogrammed
> once a year, just in case.

So, you're assuming the EEPROM contents will remain intact
between times that you get a chance to "examine" it.  Note
that there are no CRC's on the configuration so if a bit
toggles, you'll have no way of knowing that the configuration
has changed and will gleefully "refresh" it to its erroneous
state.

[Unless you leverage the discarded EEPROM store to keep
a highly redundant copy of that information]

>> Why not just opt for a one-wire ADC?
>
> Where, on the module? It's exactly how 2438 is going to be used.

Same way as yours is used.  I'm just eliding the "charge accumulator",
voltage/current monitoring, etc. that makes the 2438 so "special".

>> Or, some discrete logic that you clock, remotely?
>
> Too big.

Masked FPGA/PAL/etc.?

>> (presumably, you have some time to query the system's
>> configuration -- you're not trying to hot swap cards
>> and bring them on-line "instantly"?)
>
> Yes, no hot-swap capability required.
>
>> So, you're prepared to do an end-of-life buy as you head
>> into initial production?
>
> I can add a spare DS2438 in a bag for every produced module.

That seems like you're planning for failure -- instead of planning
for *success*!

>> What about masked parts?
>
> The scale is far to small, can't afford.

Can't argue with that!  :>

Back to sci.electronics.design | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Identification of modules Piotr Wyderski <peter.pan@neverland.mil> - 2017-03-31 09:21 +0200
  Re: Identification of modules Don Y <blockedofcourse@foo.invalid> - 2017-03-31 01:31 -0700
    Re: Identification of modules Piotr Wyderski <peter.pan@neverland.mil> - 2017-03-31 10:36 +0200
      Re: Identification of modules Don Y <blockedofcourse@foo.invalid> - 2017-03-31 02:16 -0700
        Re: Identification of modules Piotr Wyderski <peter.pan@neverland.mil> - 2017-03-31 11:39 +0200
          Re: Identification of modules Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-03-31 11:32 +0100
            Re: Identification of modules Piotr Wyderski <peter.pan@neverland.mil> - 2017-03-31 12:59 +0200
          Re: Identification of modules Don Y <blockedofcourse@foo.invalid> - 2017-03-31 11:55 -0700
    Re: Identification of modules Piotr Wyderski <peter.pan@neverland.mil> - 2017-03-31 11:30 +0200
  Re: Identification of modules rickman <gnuarm@gmail.com> - 2017-03-31 05:20 -0400
    Re: Identification of modules Piotr Wyderski <peter.pan@neverland.mil> - 2017-03-31 11:53 +0200
      Re: Identification of modules rickman <gnuarm@gmail.com> - 2017-03-31 06:16 -0400
        Re: Identification of modules Piotr Wyderski <peter.pan@neverland.mil> - 2017-03-31 12:39 +0200
          Re: Identification of modules rickman <gnuarm@gmail.com> - 2017-03-31 13:27 -0400
            Re: Identification of modules Piotr Wyderski <peter.pan@neverland.mil> - 2017-03-31 22:14 +0200
              Re: Identification of modules rickman <gnuarm@gmail.com> - 2017-03-31 17:48 -0400
                Re: Identification of modules Piotr Wyderski <peter.pan@neverland.mil> - 2017-04-03 10:57 +0200
    Re: Identification of modules John Devereux <john@devereux.me.uk> - 2017-03-31 11:39 +0100
      Re: Identification of modules rickman <gnuarm@gmail.com> - 2017-03-31 13:38 -0400
        Re: Identification of modules Piotr Wyderski <peter.pan@neverland.mil> - 2017-03-31 22:21 +0200
  Re: Identification of modules Joe Chisolm <jchisolm6@earthlink.net> - 2017-03-31 13:02 -0500
  Re: Identification of modules Tim Wescott <seemywebsite@myfooter.really> - 2017-03-31 16:18 -0500

csiph-web