SD card data storage questions
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From: Richard Rasker on 13 Apr 2010 05:41 Hello, I'm working on a stand-alone, battery-powered temperature monitoring device which collects a few megabytes of data over the course of a few weeks. The goal is to monitor the temperature of bearings and a clutch box of a heavy machine under varying loads, and evaluate these measurements afterwards. Most of this is a trival design matter, and I got almost everything running just fine within a few days. The only problem I'm still facing is data storage: I'd like to use an SD card (or Micro SD) to store this data, so that the user can transfer the data to a PC with minimal hassle. My questions: - It would appear that I need a license from the SD Card Association if I want to build (and sell) anything containing an SD card host circuit (see http://www.sdcard.org/developers/join/licensing/ "Host and Ancillary Products"). Now this would more than triple my development cost, in fact making it rather uneconomical to use SD cards -- this temperature monitor isn't meant to be built in any significant numbers (three, to be exact). Does anyone know more about these licensing requirements? - Does anyone have any information on how to write data to SD cards using a PIC controller? Any suggestions for a different data storage and retrieval mechanism are welcome too, of course, but I can't think of anything as easy to use as an SD card. Also, I'd rather not use a USB device, because the whole shazzam now runs off a 3V power source, whereas USB requires 5 volts. Thanks in advance for any suggestions, best regards, Richard Rasker -- http://www.linetec.nl
From: MK on 13 Apr 2010 06:24 "Richard Rasker" <spamtrap(a)linetec.nl> wrote in message news:4bc43c4c$0$729$7ade8c0d(a)textreader.nntp.internl.net... > Hello, > > I'm working on a stand-alone, battery-powered temperature monitoring > device > which collects a few megabytes of data over the course of a few weeks. The > goal is to monitor the temperature of bearings and a clutch box of a heavy > machine under varying loads, and evaluate these measurements afterwards. > Most of this is a trival design matter, and I got almost everything > running > just fine within a few days. > The only problem I'm still facing is data storage: I'd like to use an SD > card (or Micro SD) to store this data, so that the user can transfer the > data to a PC with minimal hassle. > > My questions: > - It would appear that I need a license from the SD Card Association if I > want to build (and sell) anything containing an SD card host circuit (see > http://www.sdcard.org/developers/join/licensing/ "Host and Ancillary > Products"). Now this would more than triple my development cost, in fact > making it rather uneconomical to use SD cards -- this temperature monitor > isn't meant to be built in any significant numbers (three, to be exact). > Does anyone know more about these licensing requirements? > - Does anyone have any information on how to write data to SD cards using > a > PIC controller? > > Any suggestions for a different data storage and retrieval mechanism are > welcome too, of course, but I can't think of anything as easy to use as an > SD card. Also, I'd rather not use a USB device, because the whole shazzam > now runs off a 3V power source, whereas USB requires 5 volts. > > Thanks in advance for any suggestions, best regards, > > Richard Rasker > -- > http://www.linetec.nl Use a soldered in serial access Flash (Farnell have 1535453 16Mbytes for �9) and dump the data to the PC via a serial port. Cheap and easy. The serial port dump will be a bit slow (about half an hour for 16Mbytes @ 115.2kb) but that should be OK for the use you describe. Michael Kellett
From: Tim Williams on 13 Apr 2010 07:12 CF cards may be easier to use? Just an IDE interface I think. Not exactly "compact" by today's standards, of course... Tim -- Deep Friar: a very philosophical monk. Website: http://webpages.charter.net/dawill/tmoranwms "Richard Rasker" <spamtrap(a)linetec.nl> wrote in message news:4bc43c4c$0$729$7ade8c0d(a)textreader.nntp.internl.net... > Hello, > > I'm working on a stand-alone, battery-powered temperature monitoring > device > which collects a few megabytes of data over the course of a few weeks. The > goal is to monitor the temperature of bearings and a clutch box of a heavy > machine under varying loads, and evaluate these measurements afterwards. > Most of this is a trival design matter, and I got almost everything > running > just fine within a few days. > The only problem I'm still facing is data storage: I'd like to use an SD > card (or Micro SD) to store this data, so that the user can transfer the > data to a PC with minimal hassle. > > My questions: > - It would appear that I need a license from the SD Card Association if I > want to build (and sell) anything containing an SD card host circuit (see > http://www.sdcard.org/developers/join/licensing/ "Host and Ancillary > Products"). Now this would more than triple my development cost, in fact > making it rather uneconomical to use SD cards -- this temperature monitor > isn't meant to be built in any significant numbers (three, to be exact). > Does anyone know more about these licensing requirements? > - Does anyone have any information on how to write data to SD cards using > a > PIC controller? > > Any suggestions for a different data storage and retrieval mechanism are > welcome too, of course, but I can't think of anything as easy to use as an > SD card. Also, I'd rather not use a USB device, because the whole shazzam > now runs off a 3V power source, whereas USB requires 5 volts. > > Thanks in advance for any suggestions, best regards, > > Richard Rasker > -- > http://www.linetec.nl
From: Royston Vasey on 13 Apr 2010 07:36 "Tim Williams" <tmoranwms(a)charter.net> wrote in message news:hq1jjo$hht$1(a)news.eternal-september.org... > CF cards may be easier to use? Just an IDE interface I think. Not > exactly "compact" by today's standards, of course... > > Tim > > -- > Deep Friar: a very philosophical monk. > Website: http://webpages.charter.net/dawill/tmoranwms > > "Richard Rasker" <spamtrap(a)linetec.nl> wrote in message > news:4bc43c4c$0$729$7ade8c0d(a)textreader.nntp.internl.net... >> Hello, >> >> I'm working on a stand-alone, battery-powered temperature monitoring >> device >> which collects a few megabytes of data over the course of a few weeks. >> The >> goal is to monitor the temperature of bearings and a clutch box of a >> heavy >> machine under varying loads, and evaluate these measurements afterwards. >> Most of this is a trival design matter, and I got almost everything >> running >> just fine within a few days. >> The only problem I'm still facing is data storage: I'd like to use an SD >> card (or Micro SD) to store this data, so that the user can transfer the >> data to a PC with minimal hassle. >> >> My questions: >> - It would appear that I need a license from the SD Card Association if I >> want to build (and sell) anything containing an SD card host circuit (see >> http://www.sdcard.org/developers/join/licensing/ "Host and Ancillary >> Products"). Now this would more than triple my development cost, in fact >> making it rather uneconomical to use SD cards -- this temperature monitor >> isn't meant to be built in any significant numbers (three, to be exact). >> Does anyone know more about these licensing requirements? >> - Does anyone have any information on how to write data to SD cards using >> a >> PIC controller? >> >> Any suggestions for a different data storage and retrieval mechanism are >> welcome too, of course, but I can't think of anything as easy to use as >> an >> SD card. Also, I'd rather not use a USB device, because the whole shazzam >> now runs off a 3V power source, whereas USB requires 5 volts. >> >> Thanks in advance for any suggestions, best regards, >> >> Richard Rasker >> -- >> http://www.linetec.nl > > or MMC, IIRC the interface is easily PICable.
From: Adrian C on 13 Apr 2010 07:47
On 13/04/2010 10:41, Richard Rasker wrote: > The only problem I'm still facing is data storage: I'd like to use an SD > card (or Micro SD) to store this data, so that the user can transfer the > data to a PC with minimal hassle. Is selling a SD compatible device without joining the SD Card association really something you can get fined for? What about a USB client port, and allow the use of USB thumb drives. Or, do ye have to forcibly join the USB association for that ... -- Adrian C |