it's much much easier to find fast SD cards - MMC should work in my camera as well, but the fastest rs-mmc I found is 88x - unfortunately after I purchased my dog slow Kingston 1GB 1.5MB/s..., my 1GB SD is 133x (~18 - 20MB/s) and that makes a big difference on a usb2.0 card reader. Moreso compared to 1.5MB/s.
Yes, that's true now. (RS-)MMC uses 7 pins and only 1 for data transfer. This is really old and outdated standard. SD uses 9 pins and 4 for data transfer. Newer MMCmobile, backward compatible with rs-mmc uses 13 pins and 8 for data transfer. Problem is that current USB readers on market can handle only MMC and SD protocol. MMCmobile in current reader uses maybe 4 but most probably only 1 pin. I have two USB readers (both cheap in ~5$ range) and one does 1.5MB/s for all mmc and my newer 2GB kingston mmcmobile, second one does 1.5MB for mmc but 3.8MB/s for mmcmobile both for reading and writing. I have ordered
(supposedly) next generation reader (also cheap) with all 13 mmcplus pins http://www.sharkoon.com/enghtml/usb.htm#xcplus that could read even newer mmcmobile cards faster.
As for others, your ignorance does not mean the format is not used ;-) At least here in Europe MMC cards are not rare at all.
MMC derived formats are a bit older than SD and are specified by MMC association http://www.mmca.org/home (nothing realated to Nokia) Current MMC 4.1 format is better than SD and the standard is open. There is no reason this format will die in any near future.
SD cards are specified by http://www.sdcard.org/ and standard is not available unless you sign NDA and pay. That's why some linux devices didn't suport SD because the protocol was not known and there were no open source drivers for SD. Now I think something was reverse-engineered and some bits were found in various specs by manufacturers so most parts of the protocol is known. Also I think recently SD association released some stripped down specs (excluding SDMI content protection).
When Nokia explained *to me* why the 770 had RS-MMC instead of SD, their justification was that RS-MMC was what their *phones* used
Yes I heard similar thing. They took already existing parts already sitting on their shelves which they used for phones at that time.
Originally Posted by Mike Cane
hence people could, for example, take a phonecam pic and xfer it to the 770.
Well that's probably afterthought and not the main reason. You can use bluetooth for that and browse pictures directly from N770 without removing card from phone.
Originally Posted by Mike Cane
That can't happen now, can it
As for normal cameras If you use SD card then obviously not. If you use MMC/MMCplus/RS-MMC/MMCmobile in camera then yes. Also in IT2006 big MMC cards are readable without closing the door.
As for the RS-MMC slot, this was one thing I hate too. I was thinking quite hard before geting N770 due to this slot. But replacing it with microSD as you suggest is not much better.
BTW I have just read the Specification 4.x Application Notes PDF and it seem even for 1 bit transfer there could be speedup when chaging 20Mhz bus speed to 52Mhz which should give 260%. 1.5MB/s*2.6=3.9MB/s which is what I noticed in one of my USB readers. And this is over 1 wire so if OMAP 1710 chip inside 770 can switch MMC bus speed from 20 to 52Mhz for high speed cards, we could have this speed even with plain old rs-mmc connector in N770. Needs nontrivial kernel modification of course :-)
I have ordered (supposedly) next generation reader (also cheap) with all 13 mmcplus pins http://www.sharkoon.com/enghtml/usb.htm#xcplus that could read even newer mmcmobile cards faster.
Interesting. How do you like it? It seems not even prudent to get card reader built-in to computer any more since it likely to have slower transfer spped than this device.
Interesting. How do you like it? It seems not even prudent to get card reader built-in to computer any more since it likely to have slower transfer spped than this device.
I'm still waiting for it. It was out of stock and I didn't find alternative. I hope it will arrive tomorrow.
As for N770 speed - sad thing is that N770 USB connection seems to use only USB 1.1 speed and it looks like hardware limitation i.e. the USB chip is in fact 1.1. Looks like they corrected it in technical specifications http://europe.nokia.com/A4145105 since I asked. The '(with speeds up to 12Mbps)' part wasn't there last week. So you can't use N770 as fast usb card reader.
The limitations of 770 in transferring file through MMC or USB interface is unfortunate. Remarkable that wireless is the fastest way to transfer a file.
I am having trouble finding other MMC 4.1 readers. An internal (to PC) reader would be OK for wiFi transfer to 770, but typically only the USB dongle type readers give out their specs.
