Cradle Connectors

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The m:robe cradle is needed (and the only possibility) to charge your m:robe and to use the AV-Output.

Since Olympus does no longer support it's players, it's hard to get accessory in case of damage or lost.

So we are searching for alternatives to the cradle.



The connector that is used in the cradle is a 18-pin connector form "HRS" (Hirose Electronics) and has the partnumber "ST80 B" (see

If I can get a small number of these connectors, I can try and work on a replacement to charge - and maybe also the use the video-out without the cradle.


I've taken apart the USB cable and the cradle. I'll post images and full cradle schematics later; meanwhile here are the pinouts -- User:cben

WARNING: taking apart the USB cable is easy but putting it back without damage is very tricky! I broke the connection to the shielding, which is not that important electrically but quite important mechanically. Now my cable rotates freely at the point it enters the connector, and it worries me :-( Please don't try this yourself at least until I post photos of the damage.

Order: on the player and at the back of the cradle, pin 1 is the rightmost pin. 18 is closest to the remote connector on the player.

Pin USB cable cradle-USB cradle-player notes
3 GND in player
4 DC 5V
5 DC 5V
6 white D- D-
7 AV GND outer sleeve of AV connector
8 Video middle ring of AV connector
9 Audio Left tip of AV connector
10 Audio Right forward ring of AV connector
11 unkown
12 DC 5V
13 green D+ D+
14 GND(?) GND in player
15 connected unknown apparently important
16 connected unknown apparently important
17 black GND GND
18 black GND GND

Charging without cradle

I think it is OK to short the DC 5V pins to VBUS pins of the USB cable, so that I can charge directly with the USB cable. The only drawback to that (and the probable reason why Olympus didn't do this) is that USB only allows taking 500mA and only if the device requested it, while the DC supply is rated for 2A. So doing this violates the USB spec - but should be OK with most PCs, they don't really limit the current.

  • TODO: measure actual consumption while charging.
  • Q: do laptops enforce USB current limits?
  • Q: is the USB cable rated for 2A?

Anyway, I recommend you don't try this until I post my results -- User:cben

Video-out without cradle?

The tip-and-3-rings connector for the remote is unfortunately (and confusingly) not stereo+video but stereo+reset :-(. This means that you can only watch the video-out through the cradle.

I don't see a good easy way to work around that:

  • If you can obtaing new plugs, then preparing a custom cable (player to 3 RCA plugs) looks like a good idea. However, you can't use it and USB at the same time.
  • Soldering new leads out of the USB cable is possible but ugly, and I'm afraid it might give sub-optimal signal integrity.

Hidden interface?

Does the cradle connector contain any hidden interface not accessible by the regular cradle? Apparently yes! Note that they bothered to connect pins 15 and 16 from the cradle-player connector to the cradle-USB cable connector. They didn't do it for other pins, only USB pins and 15,16. This implies that Olympus has some undocumented use for them (through some special cable), and wanted them use to be accessible through the cradle as well.

My hope is that these pins allow writing to the flash in some way. If so, we could rescue bricked players, which means we wouldn't have to be afraid of bricking. No idea how to discover the interface though.

As for pin 11, my guess is that it's simply unused.

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