iriver h1x0 - RTC (real time clock) mod

[roolku]

I just read in the data sheet that a diode in series with the VCC backup should NOT be used or improper operation will result.    

Well spotted.

The data sheet also stated that the supply voltage MUST be held between 1.3 and 3.7 volts, so I will choose either the resistor or a small lithium button cell.

I wonder if this is an error/omission in the data sheet. Looking at a similar chip (DS1340 - an alternative if you don't need the alarm) it states http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3914 :

VBACKUP
Connection for a Secondary Power Supply. For the 1.8V and 3V devices, VBACKUP must be held between
1.3V and 3.7V for proper operation. Diodes placed in series between the supply and the input pin may
result in improper operation. VBACKUP can be as high as 5.5V on the 3.3V device.

Which would make more sense...

[IpaqMan]

I tend to agree with you that this may be an omission on some data sheets.  Some data sheets specify ranges for different models for Vbatt.  But some have only one range 39c/38.  Since your Hxxx players are working with the 4.2 volt input, I think that this confirms it.

One would think that if the main circuits can handle VCC up to 5.5 then the backup input should be able to do the same.

[roolku]

I just received a couple of the RTC chips and hope to do the mod later this week.  

Just curious how you are getting on. Did you get a chance to try it?

[IpaqMan]

I haven't done it yet.  

I am a several steps along the way.

1) Got RTC chip

2) Installed VMMWare Rockbox

3) Downloaded rtc.patch

4) Got successful build with rtc.patch

5) Rounded up very small gauge wires and twelve watt soldering iron

Now I need some alone time to solder.

***EDIT

6) Attached wires and tape to the RTC chip

The soldering turned out to be fairly difficult.  I think I need even smaller gauge wire than I am using now.  I would prefer a gauge so small that moving the wires would not put any stress on any solder points.  The wire I am using now is about the same size as the chip leads and is solid.

[roolku]

The soldering turned out to be fairly difficult.  I think I need even smaller gauge wire than I am using now.  I would prefer a gauge so small that moving the wires would not put any stress on any solder points.  The wire I am using now is about the same size as the chip leads and is solid.

Yes, I agree, the leverage of the wire is very stressfull for the little pins. I used stranded wire with maybe 6 very thin strands (ripped from an old mouse cable). But still the wire really needs to be kept in a fixed position without any tension once attached.

I made little 90 degree bends, and placed the wire on the chip (legs up) with the wire tip pointing outwards above the pin. While pressing the wire onto the chip and holding it in position with one  hand I use the other to dip the prepared soldering iron onto the wire tip to make the bond.

Good luck

[Peter200lx]

Well, I've installed the chip (Without the alarm mod for now) and have a patched version of rockbox, but it's still not showing time anywhere. I applied the rtc_with_alarm.patch . I even have gone to /General Settings/System , but there is no set time option. I am using rockbox with flashed firmware, could that be the problem? If you have any ideas, please tell me.

--EDIT--

ACK I didn't notice that I needed to uncomment those two lines, clock is working, and as soon as I sodder the alarm button on, I can test that! Thanks A Lot!!!

[roolku]

ACK I didn't notice that I needed to uncomment those two lines, clock is working, and as soon as I sodder the alarm button on, I can test that! Thanks A Lot!!!

Glad to hear it worked!

Roolku

[Peter200lx]

Well, did some further testing and the clock is working great, tested the clock plugin and scrobbler and such, working great. The one caveat is that the alarm isn't working in any way. Right now I just have that wire going nowhere. Whenever I hook it up it starts the last song and play/pauses it forever. I have a patched firmware with both of those two lines uncommented, so I thought that it took care of that. Any ideas?

[roolku]

Whenever I hook it up it starts the last song and play/pauses it forever. I have a patched firmware with both of those two lines uncommented, so I thought that it took care of that. Any ideas?

Rockbox with the the alarm mod patched and enabled should disable the alarm pin on start-up. So you can check that you have the menu entry "wake-up alarm" under General Settings/System.

Also you might want to double check that you haven't accidentally shortened the SQW/INT pin with another one (i.e. the SCL) when soldering on the wire.

That is all I can think of at the moment.

Roolku

[IpaqMan]

I finally had success with the mod!

However, it was a sobering experience.  My first attempt resulted in an H120 that would not power on.  Resetting the H120 did not work.  I thought I bricked it.  I disconnected the mod and still it would not power on even with a reset.  But about a half hour later I tried plugging it into a charger and it powered on!

BTW, I followed the suggestion about using mouse wires.  I found an old serial connected mouse and cut up the cable to obtain the thin flexible wires inside.

I decided that since my first attempt did not permanently brick it that I could try again.  This time I looked for another Vbackup source other than the power connector on the other side of the mainboard.  I found a source that was the same voltage as the battery.  The bottom right of the mainboard (oriented with the headphone jack on top) has two square solder coated objects.  The rightmost of the two has a 4.1 volt reading, so I decided to use that solder point.  It saves unscrewing the mainboard and flexing more leads and routing the Vbackup wire around the board.

This time I tried to be very careful of where the dangling unsoldered wires wandered about the board.  Everything went fine and the clock plugin started working.  It did not work without the RTC chip installed.

BTW, I like the date-time naming of the recorded filenames.  That avoids problems with editing the file contents and changing the date-time modified value.

Overall, using the flexible mouse wires and using the new Vbackup source made the project relatively easy.

[roolku]

I finally had success with the mod!

Well done.

If you don't mind I will transfer some of your experiences to the wiki (when the site is back up).

[IpaqMan]

I finally had success with the mod!

Well done.

If you don't mind I will transfer some of your experiences to the wiki (when the site is back up).

No problem.  Anything to help.  Maybe this can encourage others to look for more easy solder points.

BTW, to clarify, the Vbackup solder point is at the bottom right of the mainboard when the board is oriented with the headphone jack uppermost.

[flintstone]

If the alarm function works properly now,
would it be possible (...he asked with
trembling hands...) to add a patch
that started and stopped recording
based on the time of day?

I've got a project that needs a way to
automatically record for a few minutes, then
wait for a specified time, record, wait,
record, and so on.   Duration of recording
limited only by disc space and battery life.

It may be simplest to set the recording time
and the waiting interval from a text file (start
at 8:00, stop at 8:10, start at 9:45, stop at 9:58,
and so on).

There are a couple of commercial solutions
to this problem.  They are either inflexible
(recording starts and stops at fixed intervals),
unreliable, or very expensive (often all three).

I would be very willing to pay for development
time, or to donate an amount to support the
community forums, to get this capability added.

To reply to me privately, send email to xyz at
muchomail com. Substitute my name below for
the xyz.

Many thanks, and Happy Holidays to all.

Flintstone

[jmdearras]

Well, did some further testing and the clock is working great, tested the clock plugin and scrobbler and such, working great. The one caveat is that the alarm isn't working in any way. Right now I just have that wire going nowhere. Whenever I hook it up it starts the last song and play/pauses it forever. I have a patched firmware with both of those two lines uncommented, so I thought that it took care of that. Any ideas?

I had the same issue.  Something is not working in the init code.  I managed to set an alarm with the remote, after locking the main keyboard, and that stopped the toggleing.

YBIC,
Jim

[LinusN]

I think it was a bad idea to choose a chip that outputs a waveform on the alarm pin by default.