My design for a 8 MByte Data Logger

Not heard of a SmartMedia® card (SSFDC)? - See :-

The cards current come in 0.5 to 16 MByte sizes, (not as big as compact flash cards, but cheaper, byte for byte) and larger sizes planned! Being just half the size of a credit card and flash based, they're just great for data loggers, monitors and 'black-boxes' - just slip the card into the remote monitoring equipment (eg a weather station or system history logger), leave it recording until full (3 months for an 8MByte card, at 1 Byte per second) or an event occurs (a "black box" data recorder), then swap it for a new card, and read the full card straight into your PC or laptop in the field or back at base.

So what's the advantage of SSFDC over other forms of flash, or other methods of data storage?

It's a slip it into your pocket solution - No cables or laptop required to get the data from the field to base. (although don't stick it in your trouser pocket and sit on it! - If you're going to do that, see MultiMediaCards, that are smaller and thicker :-] )
The cards are cheap and easily available - MP3 players and digital cameras use them, so pricing should be commodity; if you can't get a card at the electronics store, you can always nip down the camera shop or music store!
The card is byte-wide - making it faster than serial based cards - but has only 8 data, a status and six control pins, making it easy to connect to microcontrollers - cf. A29F080 which has 34 data/control pins!
the internal NAND flash stucture requires a smaller chip than the equivalent density in other flash stuctures.

This is why I started designing a SSFDC data logger circuit.

SSFDC (SmartMedia®) Info.

NAND Flash Pinout

Pin no.	Pin Name	SSDFC pinout	NAND Flash Pin no.
1, 10, 11	Vss	Ground	1, 22
2	CLE	Command Latch Enable	2
3	ALE	Address Latch Enable	3
4	WE#	Write Enable	4
5	WP#	Write Protect	5
6 - 9	I/O 1 - 4	I/O Port	18 - 21
13 - 16	I/O 5 - 8	I/O Port	24 - 27
17	LVD	Low Voltage Detect
18	SE# (*)	Spare Area Enable	40
19	R/B#	Ready / Busy	41
20	RE#	Read Enable	42
21	CE#	Chip Enable	43
22, 12	Vcc	Power Supply	23, 44 (**)

(*) - Not on some SSFDC (Gnd instead)
(**) - Pin 44 is VccQ (O/P Buffer Supply) on some NAND Flash

Sadly this project went ON HOLD in 1998, as SmartMedia has not taken off and because I didn't have the smartmedia file format nailed down - It has now taken off, and I now know the format to be FAT12/16 (dependant on size). I'm hoping sometime to complete the project, work permitting. In the 1st instance, the project may use an AVR, not a PIC

For a look at the other options for data loggers see my data logger page

The incomplete 1998 circuit diagram for the data-logger based on a PIC.

The incomplete 1998 circuit diagram for the PC Smartmedia reader/writer has been removed as there is no good reason not to use a standard parallel or USB port Smartmedia card reader now. (subject to getting the FAT format correct!)

Other sources of SSFDC and SmartMedia information

Web info. is a bit scarce at the moment, as it is that new, and most info. is just press releases:-

The SSFDC organisation web pages. These have now been updated AND MORE IMPORTANTLY, have pdfs giving the physical, logical, electrical and format specifications. (only after you have given full details of yourself etc. Also the PDFs are password protected - the password is give on the download screen; don't forget it :-)

A Reference design by Troubador This is a design for a PCMCIA card with NAND Flash Disk and Serial port, with a .PDF that gives full details of NAND Flash and software code. It refers to a discontinued Nat Semi NAND Flash part, which is identical to the Samsung and Tosh. parts.

For Information on NAND Flash, see SAMSUNG Data Book 1160-5121 for 4Mb to 128Mb - Talk to your local SAMSUNG rep.

Data sheets are now on the web - see either SAMSUNG, or TOSHIBA

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Last Updated by Steve Lawther on Saturday, 26 February, 2000 at 6:05 PM.

My design for a 8 MByte Data Logger

SSFDC (SmartMedia®) Info.

Other sources of SSFDC and SmartMedia information

SmartMedia is the Trade Mark of Toshiba. Samsung and Toshiba are Trade Marks