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Recommendation for setting CONFIG_ETRAX_DS1302_TRICKLE_CHARGE ?



Hello,

In reference to an earlier post (see below), can someone at Axis recommend a
setting to use for CONFIG_ETRAX_DS1302_TRICKLE_CHARGE ?

I am developing for device server 82/83 and need the clock to be correct
after cycling power.

Am I correct to assume that the clock loses its time after a power cycle
with the default factory settings?

Thanks,

-Randy
 
-----Original Message-----
From: owner-dev-etrax@xxxxxxx.com">mailto:owner-dev-etrax@xxxxxxx.com] On Behalf
Of Johan Adolfsson
Sent: Thursday, August 19, 2004 1:41 PM
To: dev-etrax@xxxxxxx.com; Frank Brown
Subject: Re: DateTime lost between reboots. 

Just to clarify, the devboard_82 has a battery and the
devboard_lx has a capacitor.
There is a since some time a kernelconfig option to configure
how the capacitor should be charged so you don't need to use
hwtestrtc for that.

CONFIG_ETRAX_DS1302_TRICKLE_CHARGE
  This controls the initial value of the trickle charge register.
  0 = disabled (use this if you are unsure or have a non rechargable
battery)
  Otherwise the following values can be OR:ed together to control the
  charge current:
  1 = 2kohm, 2 = 4kohm, 3 = 4kohm
  4 = 1 diode, 8 = 2 diodes
  Allowed values are (increasing current): 0, 11, 10, 9, 7, 6, 5

/Johan

----- Original Message ----- 
From: "Frank Brown" <fcb3@xxxxxxx.net>
To: <dev-etrax@xxxxxxx.com>
Sent: Thursday, August 19, 2004 6:29 PM
Subject: Re: DateTime lost between reboots.


> The important reason to use hwtestrtc to set up the time
> the first time-> The Axis board uses a huge capacitor to
> maintain the clock chip. For obviously good reasons, this
> capacitor has a controllable connection for charging when
> the board is powered up. This is a rather unique function
> function, and would never be part of a generic linux program.
> Axis ships the board with this port turned off, so until you
> set it up, your clock will reset to year 2k on startup. It's a
> very good idea, but one does wish you didn't have so much
> trouble discovering it.
>
> try hwtestrtc ? to see the syntax. I set my diodes/resistor
> to a 1 (C1).
>
> f
>