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Rockbox General => Rockbox General Discussion => Topic started by: siouxes on April 18, 2011, 05:18:52 PM

Title: Ipod nano 2nd gen - white screen
Post by: siouxes on April 18, 2011, 05:18:52 PM
Hi guys,

 i have an old ipod nano 2nd generation and some days ago i read about rockbox. I am not a linux noob and i use the rockboxutility to reborn my pod to a new life.
So, i read on port status that now ipod 2nd gen is supported, since rockbox 3.7.

RockBox utility says that installation was going all done, but after reset my ipod, after the apple logo, i can read "rockbox" on the screen for a while, and than all the LCD fade to a 100% white.

The strange things, is that if i connect my earpiece, and move the clickwheel, i hear rockbox TTS that says to me in wich menu item i am!!!

So, seems to be that rockbox is working, but somethings goes wrong on LCD initialization, i think.

Just for information, i tried all version under the 'release' folder, from 3.7 to last one 3.8.1. I have also tested the latest build version with the same behaviour.
Notice that between one version to the other, i always recover my ipod via itunes, so i am sure that firmware nor files on my pod was corrupted.

I am available to any test, i really want to have rockbox installed (and working) on my ipod.

BR to all.

Simone
Title: Re: Ipod nano 2nd gen - white screen
Post by: Chronon on April 18, 2011, 08:25:35 PM
See if this helps:
http://forums.rockbox.org/index.php?topic=26365.0
Title: Re: Ipod nano 2nd gen - white screen
Post by: bertrik on April 19, 2011, 09:42:52 AM
I'm no ipod nano 2g expert, but a slow fade to white (like a blooming effect) of the LCD generally means that the display is no longer driven by the LCD controller.

It's a bit odd that you do see a rockbox logo at the start. Perhaps the logo was shown by the rockbox bootloader and the display driver is somehow not working in the main rockbox firmware.
Title: Re: Ipod nano 2nd gen - white screen
Post by: siouxes on April 19, 2011, 10:36:45 AM
Hi bertrik, from the wiki:

http://www.rockbox.org/wiki/IPodNano2GPort

in status section, says:

LCD driver    - Done - Full functionality implemented and reasonably optimized (since r28813)

I am using latest SVN source, r29749.

I think that my ipod, probably, has some hardware difference or other things that i don't know... the reason for this thread is that i googled this problem and i found other rockbox users with the same issue... so, i have some time to spent over this and i think that is good to use this time to help this project to enlarge the device compatibility.

(excuse for my english, i hope it's clear...)
Title: Re: Ipod nano 2nd gen - white screen
Post by: Chronon on April 19, 2011, 01:17:52 PM
Your English is perfectly clear.  :)

I agree that initial display of the Rockbox logo then a slow fade to white gives the appearance that the bootloader and firmware are doing something a bit differently.  Do different contrast values have any effect?
Title: Re: Ipod nano 2nd gen - white screen
Post by: siouxes on April 19, 2011, 01:27:39 PM
I don't know how to change it. From the ipod i didn't find the contrast settings (i can only use the voice guidance) and from other thread i read that it can be changed by the file config.cfg... but i didn't find it in the .rockbox directory nor into sources.
Title: Re: Ipod nano 2nd gen - white screen
Post by: Chronon on April 19, 2011, 02:13:20 PM
If you browse the .rockbox directory with your PC's file browser you don't see a config.cfg file?
Title: Re: Ipod nano 2nd gen - white screen
Post by: siouxes on April 19, 2011, 02:17:49 PM
Really not... this is the content of my .rockbox ...

Code: [Select]
user@user-ubuntu:~/Scaricati/ipodnano/rockbox/build/.rockbox$ ls -l
total 608
drwxr-xr-x 2 user user   4096 2011-04-19 01:32 backdrops
drwxr-xr-x 2 user user   4096 2011-04-19 01:32 codecs
drwxr-xr-x 2 user user   4096 2011-04-19 01:32 codepages
-rw-r--r-- 1 user user      0 2011-04-19 01:32 database.ignore
drwxr-xr-x 2 user user   4096 2011-04-19 01:32 docs
drwxr-xr-x 2 user user   4096 2011-04-19 01:32 eqs
drwxr-xr-x 2 user user   4096 2011-04-19 01:32 fonts
drwxr-xr-x 2 user user   4096 2011-04-19 01:32 icons
drwxr-xr-x 2 user user   4096 2011-04-19 01:32 langs
-rw-r--r-- 1 user user    712 2011-04-19 01:32 rockbox-info.txt
-rw-r--r-- 1 user user 553532 2011-04-19 01:32 rockbox.ipod
drwxr-xr-x 6 user user   4096 2011-04-19 01:32 rocks
-rw-r--r-- 1 user user   8896 2011-04-19 01:32 tagnavi.config
drwxr-xr-x 2 user user   4096 2011-04-19 01:32 themes
-rw-r--r-- 1 user user   1753 2011-04-19 01:32 viewers.config
drwxr-xr-x 8 user user   4096 2011-04-19 01:32 wps
Title: Re: Ipod nano 2nd gen - white screen
Post by: gbl08ma on April 19, 2011, 02:25:47 PM
BTW, iPod Nano's don't have contrast... at least, mine (2nd gen) doesn't have.

When the backlight of the screen is at its lowest value, it's still readable enough.

What can be happening is that the setting of the inactivity display shutdown is set to 0 seconds (immediately), and I don't know if that's possible, but that will leave the screen dark and shutdown, not 100% white.
Title: Re: Ipod nano 2nd gen - white screen
Post by: Chronon on April 19, 2011, 02:33:36 PM
The manual says this:
Quote
A special case configuration file can be used to force a particular setting or settings every time Rockbox starts up (e.g. to set the volume to a safe level). Format a new configuration file as above with the required setting(s) and save it into the /.rockbox directory with the filename fixed.cfg.

Try creating this file with desired contrast level in it.   Contrast is listed as a valid config option for this player, so it should work.
Title: Re: Ipod nano 2nd gen - white screen
Post by: siouxes on April 19, 2011, 02:50:20 PM
OK... somthing happens... i try to explain:

i read the manual regarding config files...
i have created fixed.cfg into .rockbox, first time only with "contrast: 0", then with "contrast: 10", then 32 and then 63; nothing changes...
after this, i try with brightness settings... lowering it to 0 makes the screen a solid gray... seems to be that in a strange way this settings really modify the display brightness...

Seems to be that the firmware can't write to the display in the right way, or perhaps make a wrong initialization... digging into the source, i found this:

Code: [Select]
/* LCD init */
void lcd_init_device(void)

#if CONFIG_LCD == LCD_IPODCOLOR
    if (IPOD_HW_REVISION == 0x60000) {
        lcd_type = 0;
    } else {
        lcd_type = (GPIOA_INPUT_VAL & 0x2) | ((GPIOA_INPUT_VAL & 0x10) >> 4);
    }
    if ((lcd_type&1) == 0) {
        lcd_cmd_data(0xef, 0x0);
        lcd_cmd_data(0x01, 0x0);
        lcd_cmd_data(0x80, 0x1);
        lcd_cmd_data(0x10, 0xc);
        lcd_cmd_data(0x18, 0x6);
        lcd_cmd_data(0x7e, 0x4);
        lcd_cmd_data(0x7e, 0x5);
        lcd_cmd_data(0x7f, 0x1);
    }
#elif CONFIG_LCD == LCD_IPODNANO
    /* iPodLinux doesn't appear have any LCD init code for the Nano */
#endif
}

this code chunk is from firmware/target/arm/ipod/lcd-color_nano.c

i don't know if it's related...
Title: Re: Ipod nano 2nd gen - white screen
Post by: Buschel on April 19, 2011, 03:03:38 PM
Can you please enter the iPod's Diagnostic Mode (first press and hold MENU + SELECT until the iPod resets, then -- during the Apple logo -- press and hold BACK + SELECT). In the Diag Mode select "Others", then "Status", then switch to the 2nd page. How are "LCD Detect0" and "LCD Detect1" set?
Title: Re: Ipod nano 2nd gen - white screen
Post by: siouxes on April 19, 2011, 03:17:02 PM
LCD Detect0:1
and
LCD Detect1:0

...i have tried also with LCD->color pattern and i correctly see some graphicals page... in the LCD->brightness control i can correctly switch on and off the backlight...
Title: Re: Ipod nano 2nd gen - white screen
Post by: Buschel on April 19, 2011, 03:19:39 PM
Strange, same LCD type as mine... Mine works since ages. Can you compile rockbox on your own?
Title: Re: Ipod nano 2nd gen - white screen
Post by: siouxes on April 19, 2011, 03:21:44 PM
yes... i have already compiled from source and now i am doing all this tests with r29749.. from SVN...
Title: Re: Ipod nano 2nd gen - white screen
Post by: Buschel on April 19, 2011, 03:25:29 PM
good. can you please do a simple test and comment line 49 in firmware/target/arm/s5l8700/ipodnano2g/power-nano2g.c ? This is something like "pmu_ldo_set_voltage blabla"..
Title: Re: Ipod nano 2nd gen - white screen
Post by: siouxes on April 19, 2011, 03:34:08 PM
WOW... now works! you're a guru!  :D

i speak to much earlier... when restore from stand by is all white... :-(

OK... the complete behaviour is:

at power on: all works.
go to stand by while hold is off
restore from stand by, for example using the action key: all white.
from all white, is i put hold to on and then to off... all works again...

btw... i am satisfied... for me is acceptable...
tell me if you want to do other tests...
Title: Re: Ipod nano 2nd gen - white screen
Post by: Buschel on April 19, 2011, 03:37:01 PM
Really? In fact I didn't expect this, just was an idea as this was one of the early changes to the LCD before v3.7 ...
Nevertheless: Good news! :)

Now we need to find out how low you can go with the voltage supply. Reason is that my (and other users nano's) make a disturbing humming noise when the voltage is not lowered. Can you try to experiment a bit a see from what voltage on your controller works?
Title: Re: Ipod nano 2nd gen - white screen
Post by: gbl08ma on April 19, 2011, 03:37:50 PM
Ha! that Rockbox LCD voltage changes that took place long ago work nicely on most of our devices but not on all the devices... for some reason Apple set the default voltage to the max supported by the displays!

And now? I don't want to have that buzzing sound on the display again! How can this be solved (having all displays working, without buzz sound on most of them).


(Oops: Buschel came first. Here's my post anyways.)
Title: Re: Ipod nano 2nd gen - white screen
Post by: siouxes on April 19, 2011, 03:39:39 PM
ok... i'll make some usage test and came back to you as soon as possibile... now i have to go home... i am still in office... here is 22.38 (or 10:38 pm)...
Title: Re: Ipod nano 2nd gen - white screen
Post by: Buschel on April 19, 2011, 03:53:03 PM
at power on: all works.
go to stand by while hold is off
restore from stand by, for example using the action key: all white.
from all white, is i put hold to on and then to off... all works again...

You are talking of the LCD standby, right? You can disable this in the settings and keep the LCD switched on all the time (with backlight still switching off). This way you won't experience any of your issues.

Switch on and off hold will call s5l_clickwheel_init() and pmu_ldo_power_on(1) in firmware/target/arm/ipod/button-clickwheel.c Maybe you can find some time to play with those code snippets and find some interesting connections...
Title: Re: Ipod nano 2nd gen - white screen
Post by: Buschel on April 22, 2011, 02:07:01 PM
Should be fixed with r29764.
Title: Re: Ipod nano 2nd gen - white screen
Post by: o_limp on August 23, 2011, 03:07:41 AM
Hi guys. In my nano 2 gen 2 Gb  white screen after turning off the backlight. Firmware 3.9 for Nano 2. Please suggest a solution. Not easy to Use with backlight on continuously.

Post Merge: August 23, 2011, 03:23:18 AM
I installed also the current build r30341, this does not work too. Works correctly only build Version: r28159

Post Merge: August 23, 2011, 01:12:03 PM
Since there is no answer, please put a working firmware for the iPod nano version of the above r28159
Title: Re: Ipod nano 2nd gen - white screen
Post by: Buschel on August 23, 2011, 02:02:37 PM
Hi,

since r28159 there were several major changes to the nano 2G LCD driver  implemented (sleep mode, massive perfomance increase, ...). It is very hard to debug such issues as there are several different iPod hardwares available...

Step 1) Please enter the iPod's Diagnostic Mode (first press and hold MENU + SELECT until the iPod resets, then -- during the Apple logo -- press and hold BACK + SELECT). In the Diag Mode select "Others", then "Status", then switch to the 2nd page. How are "LCD Detect0" and "LCD Detect1" set?

Step 2) Is it really the "backlight off" which hurts, or the "LCD sleep"? "LCD sleep" means that the LCD is really switched into a special state -- nothing will be visible on the display. You can turn the "LCD sleep" off in the settings menu (see the manual). This way the backlight will go off, but the LCD will not be put to sleep-mode.

Step 3) Did you test all releases (3.6, 3.7, 3.8 and 3.9)?

Step 4) Are you able to compile rockbox on your own? If you are able to compile it will be extremely helpful if you could track down the change which introduced this for you.
Title: Re: Ipod nano 2nd gen - white screen
Post by: o_limp on August 23, 2011, 03:02:58 PM

1) LCD Detect0:1
   LCD Detect1:0

2) Is it really "LCD sleep", I had to disable the settings and it worked!
Thank you very much!!!

3) I tested at 3.8 and 3.9

4) Tell me how to correctly compile Roсkbox, give a link where you can read, I myself could not understand.
Need to use SVN? Compile Rockbox in Win7 or only Linux?

Thank you again for your help!!! Sorry for my bad english((

Post Merge: August 23, 2011, 03:26:28 PM
I found that the builds r28159 can not view settings Sleep (After Backlight Off). hence in the previous builds had no problems with my Nano2. Thank you again, because I can not live without Rokbox!
Title: Re: Ipod nano 2nd gen - white screen
Post by: Buschel on August 23, 2011, 03:57:08 PM
Good to see switching off "LCD sleep" solves your problem. This feature was a major one, with lots of changes. It will be hard to find the cause of the issues with your player.

1) I have the same LCD type, mine works flawless.

2) Switching off "LCD sleep" could be the final solution for you even we will not find the root cause.

3) Ok, as "LCD sleep" is the cause there is no further testing required here. This feature was first delivered with v3.8

4) As a starting point you might take a look at this: http://www.rockbox.org/wiki/DevelopmentGuide (http://www.rockbox.org/wiki/DevelopmentGuide) I strongly recommend to use a VM-ware with a Linux guest on a Win7 host. Do not use cygwin -- it is far slower and harder to configure.

To be honest: Except you are eager to learn about compiling rockbox and developing some stuff on your own you should stick with the workaorund.