[Clip+, Clip Zip, ClipV2, FuzeV2] Improve battery life, part 2

[Mihail Zenkov]

I have new idea how improve power consumption even more: add scaling for CVDD2 and PVDD1. We can set CVDD2 to low value when internal and external flash/SD at idle. Also we can set lower value for PVDD1 for lower volume.
So I have prepared new patch (hack ) and builds for tests.

So what expected?
1. Improved battery life - up to 30 hours playtime on mp3 on Clip Zip.
2. Minor improvements in audio quality at 0 dB, notable at <= -9 dB and major at > 0 dB (as with new settings clipping at high volume should be completely eliminated).
3. Freezes and bugs as always

Know problems:
1. Backlight of screen (on Clip Zip) changes brightness if flash/SD in usage and if you switch volume > 0 dB.
2. At this moment I test only DAC, so problems with ADC (recordings) or FM can be expected.

So what I want to know?
1. Is it works at all on others players? Write the name and variant (system > debug > view hw info)  of your player and result.
2. If it works without big problems - try do battery runtime testing.

http://knk.square7.ch/cvdd2/rocobox-cvdd2_scaling-0.patch

Builds with this patch + i2sout_without_dma.patch (http://forums.rockbox.org/index.php/topic,51184.0.html):
http://knk.square7.ch/cvdd2/rockbox-clip+-cvdd2_scaling-12.zip
http://knk.square7.ch/cvdd2/rockbox-clipv2-cvdd2_scaling-12.zip
http://knk.square7.ch/cvdd2/rockbox-fuzev2-cvdd2_scaling-12.zip
http://knk.square7.ch/cvdd2/rockbox-zip-cvdd2_scaling-12.zip

P.S. Don't touch new settings in debug menu (*VDD*) if you not sure what you doing


Technical details:

PVDD1 derived from CVDD2.
PVDD1 used by digital part of DAC and ADC.
CVDD2 used by for flash, SD, RAM and probably OLED, some part of USB (and maybe something else). At now I can't set lower value for CVDD2 due internal flash instability. But I still hope to find solution and got 40 hours from Clip Zip at some day

Audio settings:

AVDD17 derived from AVDD27.
AVDD17 used by analog part of DAC and ADC. Also used by others analog parts. If we rise it we got bigger maximum output volume. But at some point we got clipping. So I tune CVDD2, PVDD1 and AVDD17 for get maximum possible volume without clipping. Lower value of PVDD1 consume less power and slightly improving THD/IMD but at very low value we got clipping - so best value depend from volume.

All measurements (more than 100 measurements) was done with RMAA and Emu0204 with load 32 om.

I also checked again AUDIOSET2_HPH_QUALITY_HIGH + AUDIOSET3_HP_BIAS_150.  It consume only 0.2 mA. At high volume (>= 0 dB)  mostly no difference in audio quality. But if volume <= -9 dB we have notable improvement (THD better for 35%).

[asymsucon]

Thanks for this, will test this ASAP!
Newb question - apart from replacing everything in .rockbox with this, are there any more steps necessary for successful boot?

[johnb]

No, just shut down once after copying over.

[asymsucon]

I'm experiencing freezing when trying to play any sort of file (all Opus in my case).
Edit: It took approx. 2 minutes to load single Opus file. No change even with FLAC.
Basically everything takes more time (even shutting down)

Running on Clip+

[Mihail Zenkov]

Which exactly variant of clip+ you have (system > debug > view hw info)?

[asymsucon]

[Submodel:]
AMSv2 variant 1

Edit: Output is notably increased with this mod. 1041mVrms with no distortion. Bravo!
Battery seems to be reporting about the same values as before, though no testing was done yet.

[Mihail Zenkov]

Try this: http://knk.square7.ch/cvdd2/rockbox-clip+-cvdd2_scaling-1.zip - less power saving but probably more stability.

Edit: Output is notably increased with this mod. 1041mVrms with no distortion. Bravo!

Good But be warned: at >0 dB it consume more power than current rockbox.

Battery seems to be reporting about the same values as before, though no testing was done yet.

We are can't directly measure battery consumption from firmware. We do battery runtime testing and than just set this value to firmware.
So only battery runtime testing can show right value.

[asymsucon]

My apologies, the previous build is working OK as long as the frequency is set to 48kHz while playing Opus.
I had it set to 44.1kHz to mitigate the pitch problem from another thread. I switched it back and it's much more responsive.

Nevertheless I'll try this updated version and report back.

[asymsucon]

scaling-1 now works fine even with extra resampling in the way (48k->44.1k)

[johnb]

clip+ variant1, still reporting on the first build: works ok when running mp3 from internal memory, but fails on sd access:
with dir cache on it takes a while but the shows the top level dirs, but trying to enter an album directory it shows (if at all) as empty.
This is with a Samsung EVO 64GB card.

[Mihail Zenkov]

asymsucon, johnb:

Did you see abnormally changes in screen brightness?

[johnb]

I just returned home and tried a different card: Sandisk 128 GB.
I AM able to browse directories and play songs! With dir cache off, there is a huge lag, e.g. WPS-> File browser to even appear. Responsiveness is horrible.

With dir cache on, it's much better, but I see a delay in start of playing a song after it has been selected in file browser.

[asymsucon]

Nothing so far, even with contrast set to 50 and stressing the CPU with some extra effects (scaling-0 tested)
Running 128GB microSDXC Sandisk Ultra

[johnb]

Rg. brightness: nothing special.

Should I  continue testing more stuff with the first build or go on with your latest version?


I can also test with a variant 0, if you want me to?

-------------------
I just switched to a Kingston 8GB card: I see none of the delay and lacking responsiveness  :-)
---------------------

When decreasing from +6dB (i.e. in the + range) I hear sometimes a click (similar to transitioning the -40dB threshold).
--------------------------

the variant 0 gets a little further on the Samsung card: I can browse through the dirs and even select a song. It displays the tags in WPS, but won't ever play.

[Mihail Zenkov]

Should I  continue testing more stuff with the first build or go on with your latest version?

Can you test latest version with sd cards which have problems?

I can also test with a variant 0, if you want me to?

Yes, it can be useful.

When decreasing from +6dB (i.e. in the + range) I hear sometimes a click (similar to transitioning the -40dB threshold).

Ok, probably I know solution for this.