Temperature related wifi board problem

[pd0swl]

OK,

A tough one :-)

Since some time I have a small problem with one of my control RRCs.
It is the old (mono) version and I have a WIFI board installed.

Here's what happens:
If I start up the unit by inserting power it sometimes gets into a "start-up loop".
The red/orange light flashes, the green light just *very* briefly flashes, the audio gives a click end all repeats several times. Only after several startups the unit gets to the regular green blinking status of waiting for a connection, and eventually it finally connects to WIFI. This can be after more than 15 startup loops.

As I have 2 RRC sets I tried exchanging WIFI boards, same problem.
If I use the unit with ethernet, there is no problem at all, it connects immidiately.

Lately the problem stayed away for a while but now temperatures have dropped around this RRC to about freezing point, the problem is back again.

So....it seems this RRC has a problem acknowledging the WIFI board when temperatures are quite low.

Is there any temperature critical component I could look at?
Could it be the WIFI board somehow receives too little current so the unit wants to restart?
What regulator is supplying the WIFI board voltage?
Is there a temperature limitation for the WIFI board itself?

I realise this is a strange & difficult to analyze problem.
Any advice welcome.

73
Paul
PD0PSB

[Jan (Microbit)]

If you could connect a serial cable to COM1 and use a terminal program set at 38400 baud, 8 data bits, 1 stop bit and no parity and dump the printouts to a file for us to have a look at then maybe we are able to better help.

[pd0swl]

Thanks for reply Jan,

So, COM1 sends out diagnostics during the boot procedure?

I think I used "PortMon" a long time ago for something similar.
Should be able to give you a serial dump.

I'll report back to you.

73!
Paul
PD0PSB

[Jan (Microbit)]

Use an ordinary serial terminal program, like Hyperterminal if you have Windows XP.

[pd0swl]

Jan,

I dumped both my old and new RRC.
The old RRC (with the problem) is bootloader 1.6.
It only gives:

<20130115171654.482 RX>
€ [len=2]
<20130115171654.981 RX>
<LF>========================================== [len=43]
<20130115171654.997 RX>
<LF>** 1285/1258 Bootloader V1.6            ** [len=43]
<20130115171655.012 RX>
<LF>** Booting application                  ** [len=43]
<20130115171655.012 RX>
<LF>========================================== [len=43]
<20130115171655.028 RX>
<LF>** Press capital x for xmodem apploader ** [len=43]
<20130115171655.043 RX>
<LF>========================================== [len=43]
<20130115171655.059 RX>
<LF>

My new RRC (bootloader 1.10) gives the full diagnostics including wifi etcetera.

Could this be part of the problem?
(older bootloader?)

73!
Paul
PD0PSB

[pd0swl]

Oh yes, some more tests.

-If I remove the WIFI board, the problem is non-existent. RRC always boots up.

-Opening up the control RRC I see that immediately after WIFI boards' red led lights up, the green power led goes off.

It seems just like the RRC main board isn't able to deliver the startup power for the WIFI board.
But again, all this *only* happens with a very cold unit, if the unit stays powered on it keeps running fine.

BTW: My 2 radio RRC's, which are at a even colder location never have problems. But they are constantly under power.

73
Paul
PD0PSB

[sm2o]

I have no idea but I recommend not to switch off the power if the temperature is below zero, keep it switched on and the small heat from the components will keep it dry and the inside temperature over zero.

/mike

[Jan (Microbit)]

Paul,

The printout shows what you already have concluded, i.e that the RRC is unable to boot up normally. Lack of power could be the reason, as well as other things. But the bootloader version should not be the cause.

[pd0swl]

Hi Jan,

Funny thing is that ,after this serial dump, the RRC did boot normally.
As it was on my warm workbench ;-)

Murphy is haunting me.

I'll do a full reset and reload of FW etc and keep you posted.
Still I think there is a peak-surge somewhere at boot up (regulator?) giving me trouble.

BTW searching the forum there are a few similar cases of reboot-loops.
And they only occur at the control RRC, not the radio RRC.
The control RRC is delivering the strongest current to the backlight radio heads.

73
Paul
PD0PSB

[pd0swl]

I succeeded to get a serial dump during error.
See below.

Note that after this sequence of 9 reboots the RRC booted up normally, without giving any further serial data (?).

73
Paul
PD0PSB

<20130116152703.216 RX>
À [len=2]
<20130116152703.731 RX>
<LF>========================================== [len=43]
<20130116152703.731 RX>
<LF>** 1285/1258 Bootloader V1.6            ** [len=43]
<20130116152703.746 RX>
<LF>** Booting application                  ** [len=43]
<20130116152703.762 RX>
<LF>========================================== [len=43]
<20130116152703.762 RX>
<LF>** Press capital x for xmodem apploader ** [len=43]
<20130116152703.777 RX>
<LF>========================================== [len=43]
<20130116152703.793 RX>
<LF> [len=1]
<20130116152711.328 RX>
<LF>========================================== [len=43]
<20130116152711.344 RX>
<LF>** 1285/1258 Bootloader V1.6            ** [len=43]
<20130116152711.359 RX>
<LF>** Booting application                  ** [len=43]
<20130116152711.359 RX>
<LF>========================================== [len=43]
<20130116152711.375 RX>
<LF>** Press capital x for xmodem apploader ** [len=43]
<20130116152711.390 RX>
<LF>========================================== [len=43]
<20130116152711.406 RX>
<LF> [len=1]
<20130116152718.941 RX>
<LF>========================================== [len=43]
<20130116152718.956 RX>
<LF>** 1285/1258 Bootloader V1.6            ** [len=43]
<20130116152718.956 RX>
<LF>** Booting application                  ** [len=43]
<20130116152718.972 RX>
<LF>========================================== [len=43]
<20130116152718.988 RX>
<LF>** Press capital x for xmodem apploader ** [len=43]
<20130116152719.003 RX>
<LF>========================================== [len=43]
<20130116152719.003 RX>
<LF> [len=1]
<20130116152726.554 RX>
<LF>========================================== [len=43]
<20130116152726.554 RX>
<LF>** 1285/1258 Bootloader V1.6            ** [len=43]
<20130116152726.569 RX>
<LF>** Booting application                  ** [len=43]
<20130116152726.585 RX>
<LF>========================================== [len=43]
<20130116152726.600 RX>
<LF>** Press capital x for xmodem apploader ** [len=43]
<20130116152726.600 RX>
<LF>========================================== [len=43]
<20130116152726.616 RX>
<LF> [len=1]
<20130116152734.151 RX>
<LF>========================================== [len=43]
<20130116152734.166 RX>
<LF>** 1285/1258 Bootloader V1.6            ** [len=43]
<20130116152734.182 RX>
<LF>** Booting application                  ** [len=43]
<20130116152734.198 RX>
<LF>========================================== [len=43]
<20130116152734.198 RX>
<LF>** Press capital x for xmodem apploader ** [len=43]
<20130116152734.213 RX>
<LF>========================================== [len=43]
<20130116152734.229 RX>
<LF> [len=1]
<20130116152741.764 RX>
<LF>========================================== [len=43]
<20130116152741.779 RX>
<LF>** 1285/1258 Bootloader V1.6            ** [len=43]
<20130116152741.795 RX>
<LF>** Booting application                  ** [len=43]
<20130116152741.795 RX>
<LF>========================================== [len=43]
<20130116152741.810 RX>
<LF>** Press capital x for xmodem apploader ** [len=43]
<20130116152741.826 RX>
<LF>========================================== [len=43]
<20130116152741.842 RX>
<LF> [len=1]
<20130116152749.376 RX>
<LF>========================================== [len=43]
<20130116152749.392 RX>
<LF>** 1285/1258 Bootloader V1.6            ** [len=43]
<20130116152749.392 RX>
<LF>** Booting application                  ** [len=43]
<20130116152749.408 RX>
<LF>========================================== [len=43]
<20130116152749.423 RX>
<LF>** Press capital x for xmodem apploader ** [len=43]
<20130116152749.439 RX>
<LF>========================================== [len=43]
<20130116152749.439 RX>
<LF> [len=1]
<20130116152756.989 RX>
<LF>========================================== [len=43]
<20130116152756.989 RX>
<LF>** 1285/1258 Bootloader V1.6            ** [len=43]
<20130116152757.005 RX>
<LF>** Booting application                  ** [len=43]
<20130116152757.020 RX>
<LF>========================================== [len=43]
<20130116152757.020 RX>
<LF>** Press capital x for xmodem apploader ** [len=43]
<20130116152757.036 RX>
<LF>========================================== [len=43]
<20130116152757.052 RX>
<LF> [len=1]
<20130116152804.586 RX>
<LF>========================================== [len=43]
<20130116152804.602 RX>
<LF>** 1285/1258 Bootloader V1.6            ** [len=43]
<20130116152804.618 RX>
<LF>** Booting application                  ** [len=43]
<20130116152804.618 RX>
<LF>========================================== [len=43]
<20130116152804.633 RX>
<LF>** Press capital x for xmodem apploader ** [len=43]
<20130116152804.649 RX>
<LF>========================================== [len=43]
<20130116152804.664 RX>
<LF>

[sm2o]

Yes by then the teperature inside the components has rised enough to work as normal

73 de mike

[pd0swl]

Okay.

Well it seems I have "solved" the problem by exchanging my 2 control RRCs.
I have put the new (HW version in the cold location. It always boots without problems.
I now use the old (HW version 5) in the warmer location.

Questions remain:
-Did any component change from HW V5 to V8 in terms of current management/ boot up sequence?
-Why does bootloader 1.6 give no further serial data about connection establishment etc? There is nothing to analyse in detail.

I can see several component changes from HW V5 to V8 also some around the DC converters and LF amp.

It still is strange for the unit to give problems around just -5/-10C, most components range down to -40C.
The Redpine WIFI unit should also be able to work cold.

Best 73 and thanks for thinking with me.
Paul
PD0PSB

[pd0swl]

Hi,

My remote (radio) RRC is now having the same behaviour.
It takes several minutes to boot in colder temperatures (around 5C)

Both my new version RRC with wifi board have no problems at all.
Both my old version RRC have trouble to "kick start" the Wifi boards at booting from cold.
I am quite sure the old version RRC are somehow not delivering enough startup current for the Wifi boards.

My question:
What component change was made in the new version that could relate to this?
Was a componenent taken from another manufacturer?

I would have no problem modifying the boards myself to make them behave as well as my new RRCs.

73
Paul
PD0PSB

[sm2o]

There is no changes done concerning power regulators etc. between the different versions. But we changed the ethernet PHY to a new version which has much lower power consumption, that can be the difference. Without having the documents her I think it was between v5 and v6. I think this is difficult to solve, if you absolutely has to switch off the power to the units at so low temperatures, I guess the best is to change out the older version to a new one.

73 de mike

[pd0swl]

OK thanks Mike,

My remote station is (semi) battery fed to lower the noise floor, so I switch all equipment off remotely.
I'll consider the swap to RRC V6.

I was thinking may be to feed the Wifi board by its own regulator, but I'm not sure where the main voltage is entering. I assume it is fed from the 8V line and has a 3,3V regulator on the board.
But this may be impossible since I would take the Wifi board out of the system booting & power management.

73
Paul
PD0PSB