Ratoc CFU1 USB Host

[padishah_emperor]

Has anyone actually used the following device which is supported under the new Cacko QT ROM in the C series:

Ratoc CFU1 USB Host Compact Flash card

I\'d be interested to know what actual devices are known to work with the Z, I would like to plug in:

Hard drive
CD-ROM drive
Keyboard
Mouse
Ethernet Network device

Is this doable? Are these devices available/cost effective?
If so, one of my friends can throw out the old PC he has! In fact I would only need my Debian box for a few things, it could radically change how I use my Z at home.

[vishnja]

I have this nice card, but until now I tried only mass storage devices: mp3-player, 2,5\" hd, camera...
All worked great. ;-)

[padishah_emperor]

You actually have a hard disk connected??

[vishnja]

You actually have a hard disk connected??

Yepp ;-))

It\'s nice: with the Archos gmini 220 I don\'t even need a hub or ext. powersource. The speed is great - I could listen to the mp3s on the Archos with the mediaplayer on the Z, looking at the pictures... it\'s just a mounted drive.

[padishah_emperor]

Does anyone else know if there the other items I mentioned work?  I would invest in one of these and the USB devices if I knew for a fact that they would work.

[mspencer]

Now that my C700 is back from Japan and working again, I can post my experiences with the Ratoc CFU1 USB host card.

I bought a generic USB hard disk enclosure and a 120 GB IDE hard disk for it.  (The hard disk needs a separate power adapter, but I\'m already carrying a 12 volt 18 amp-hour SLA brick and inverter in my backpack.)

1)  After fdisk\'ing you MUST reboot.  mkfs.ext2 complained about being unable to determine the size of /dev/sda1 until after I rebooted.
2)  Disk access is SLOW.  It\'s apparently mounting the drive over loopback, and loopback filesystem accesses do something nasty to the system.  (I think the whole system kinda pauses while disk accesses are running.  Will a kernel upgrade fix this?)
mkfs.ext2 took a great deal of time (I think over 20 minutes) to create a filesystem on the whole drive.
I did a really crude benchmark, since it was so slow.  From the root of that filesystem, I ran:
time dd if=/dev/zero of=/mnt/usbhd/testfile bs=1024 count=1000000
The total time came to around 29 1/2 minutes.
I did the same thing on a desktop-computer-type machine running Linux, and it completed the write in 30 seconds.
Both while creating the filesystem and while writing the test file, the Zaurus was unusably slow.  It took nearly 5 seconds to respond to any keypress or pen click.

OK, so that\'s that.

Second, I tried hooking up a Creative Labs MuVo2 4 GB (via USB, nothing taken apart), which I haven\'t disassembled yet.  (I\'m waiting until I clean off a nice photo-friendly workspace before I take the MuVo2 apart and install the 4 GB drive in the C700.  Once I do that, though, the world will gain a nice instructional video for the procedure  )  The C700 recognizes it as a hard disk with 3 partitions, (strangely) /dev/sda1, /dev/sda2, and /dev/sda4.  fdisk can see the partition table, but believes the device is much bigger than it actually is, and complains about the physical and logical begin and end not being the same, and that the partition ends on other than a cylinder boundary.  None of the partitions are mountable.

I think it\'s time someone put together a \'developers\' romdisk -- no handholding, lots of documentation, and abundant storage *required*.  I\'d love to be able to compile my own kernel in-place and build my own tools.  I want my C700 to be a *completely* self-sufficient Linux machine.

I plugged in a generic USB 802.11b adapter and it was recognized, but the syslog says no driver supports the device, or something similar.

Same messages from a USB webcam, scanner, and multi-format USB card reader (5-in-1).

A slightly larger camera ( http://externe.net/zaurus/forum/viewtopic.php?t=1123 ) is Right Out.

Plugging the C700 into itself using the sync cable didn\'t yield any amusing results.  The syslog said the USB client side stuff was timing out waiting for some kind of response, and the USB host side said it didn\'t recognize the device.

More information to come.

--Michael Spencer

[padishah_emperor]

mmh, the hard disk speed is a bit of a disappointment.  I\'m looking into getting a microdrive sometime in the near future, but please continue to post new findiings, thanks..

[tz]

You need a special version of the keyboard driver to map the keys to the Z, but any generic usb keyboard does work.  Most other things work, but you must have the specific device driver and that may need to be compiled.

[maslovsky]

The hard driver speed is in the first place limited to the speed of USB 1.1 interface, which is about 1 Mbyte/sec.
After that it\'s limited by the PCMCIA interface, which is I think even slower. So don\'t expect good performance from the USB host.

The \"special\" version of keyboard driver is included with the Cacko ROM 1.21.

[plarusa]

And how is this "special" keyboard driver loaded ? I am using the Cacko rom 1.21 + fix b with my C860 and still get the wrong keyboard mapping once I connect a USB keyboard.

Also, I see random crashes when my C860 is suspended then resumed with the USB keyboard attached.

One more thing, I can't eject the USB host card with either cardctl or the icon in the tooltray.

- Pierre.

[mspencer]

Hmm...sorry I didn't see this reply sooner, but...if the device is just being slow because it's reading more than 5 MB of data to perform an 'ls -al', then maybe it wasn't such a good idea to put a 120 MB filesystem over that slow an interface.

I'll repartition and try to make a 1 MB filesystem if possible.  I'll report if the speed changes.  In theory, if the filesystem is only 1 MB in size, and the interface supports 1 MB/sec transfer rates, and the system uses cache for I/O, then an ls-al should take no more than 1 second.  I'll confirm this.

--Michael Spencer

[maslovsky]

And how is this "special" keyboard driver loaded ? I am using the Cacko rom 1.21 + fix b with my C860 and still get the wrong keyboard mapping once I connect a USB keyboard.

For example?

Also, I see random crashes when my C860 is suspended then resumed with the USB keyboard attached

Sorry, I did not write the drivers...

One more thing, I can't eject the USB host card with either cardctl or the icon in the tooltray.

Just pool it out, it's only a USB Host card, not a storage one anyway

[papercrane]

...
(The hard disk needs a separate power adapter, but I'm already carrying a 12 volt 18 amp-hour SLA brick and inverter in my backpack.)
...

What exactly is this?

[papercrane]

Also, do you know of a battery which could drive a laptop hard drive well? A laptop HD needs ~ 5V 2.7W.

[mspencer]

That's two parts mentioned.  One:  http://www.batteriesamerica.com/newpage4.htm  (My battery is something like the upper-left one.  It's HEAVY, but I don't have to worry about running out of power.  :-)

Two:  http://www.walmart.com/catalog/product.gsp...duct_id=1818511  That's an inverter:  it converts 12V DC into 110V AC.  It's inefficient, but with such a huge battery I don't mind.  I generally get about a week of heavy usage out of that system before needing to recharge the battery.  The inverter also refuses to drain the battery down past about 40% of total capacity.  That's bad because I need more battery capacity to compensate, but that's good because lead-acid batteries don't live very long if you always drain them down to flat.

Yeah, it's heavy, but what are you going to do?  Because I'm using a USB hard disk enclosure, I need both 5V and 12V from a power supply.  I can't use a plain old battery:  I'm pretty sure a hard disk needs that voltage to hold steady, and even if I had a 5V battery it would probably give 5.5V when loaded very lightly and 4.5V when under heavy load.

So you need some kind of power regulation.  My way is less efficient, but I figure I'll have fewer problems in the long run if I just convert my battery's output to 110 V AC and use the manufacturer's own AC adapters.

If you're sure you need a smaller battery, a 2.7 watt device needs a power supply that can deliver 2.7 watts for as many hours as you need.  If you only need one hour of life, you could probably rig up 6 AAA batteries and a DC-DC switching regulator (which needs some circuitry you'll have to assemble).  That would be somewhat compact, but wouldn't have a lot of battery life.  Those 6 AAA batteries (750 mAh at 7.2 volts) provide 5.4 watt-hours if discharged slowly -- probably closer to 3 watt-hours at the speed you would need.

If you can tolerate bigger batteries, something like 6 D batteries, and don't mind spending nearly $100 for 6 top-of-the-line NiMH D cells, you can hold 9000 mAh at 7.2 volts, which is 64.8 watt-hours, which would give you about 16 hours of runtime.  (remember, you need that regulator so the output voltage stays pegged at 5 volts exactly, even as the batteries die, so you're only about 60 to 75% efficient.

I hope you see my point:  if you want to store a lot of power in a little volume you're talking about higher energy density.  Future technologies might give us better batteries with better energy density, but what we have right now gets pretty bulky.

So just do what I do:  carry around a massive tank of energy, and tolerate the increased weight.  It's good exercise.  :-)  (not so healthy for laptop bags though.  Put a towel in the bottom of your bag to avoid having holes worn through the bottom)

--Michael Spencer