SD Card Data Logger Senior Design I Mid-Semester Presentation Sep 30, 2010

Team Advisor: Dr. Patrick Donohoe James Felkins (EE) Team Leader, Testing, Web Design Harry Corey (EE) Testing, Hardware Design, Software Design Brendan Babiak (EE) Software & Hardware Design, Prototype Construction Jaron Martin (CPE) Lead Software Design, Prototype Construction

-Description of S-Drive -The Problem -The Solution -Design constraints -System overview -Tradeoffs -Timeline -Progress

The S-Drive is an OEM module that accepts data through a serial connection and saves it to an SD card.

SD cards are a viable storage medium with unique advantages but involve complex overhead.

The S-Drive will handle the unwanted overhead and make SD cards a more desirable solution.

NameDescription CommunicationThe device must have UART and SPI data connections. Voltage The device must support an input voltage between 3.3 and 5 V. Current Draw The device must draw a maximum current of 250 mA in active mode, 200 uA in sleep mode, and 10 uA in deep- sleep mode. Storage Medium The device must interface with a standard size, 32 x 24 x 2.1 mm SD card. MemoryThe device must support all SD cards up to 32 GB.

[1] SD Version NameMaximum Capacity SD 1.xSD1 GB (revised to support 4 GB) SD 2.0SDHC32 GB SD 3.0SDXC2 TB A standard-sized SD socket allows for increase compatibility across different sizes of SD cards. 32GB was chosen to support all SD cards through the SD 2.0 specification.

The device must cost less than $60. CompetitorPrice VDRIVE2$24.50 [4] Logomatic v2$59.95 [3] Avisaro M € (~$133) [2] [2] [4] [3]

The device must easily fit and integrate into other systems. Provided on a PCB No larger than 5 in 2 Easily mountable

Number of Simultaneous Open Files Allowed Convenience to the User Percent of remaining RAM available for buffer (%) How often SD card must be powered on 1Least convenient100Least often 2More convenient50More often More than 2Most convenient< 33.3Most often

PICAvailable FAT libraries? Available from Manufacturer? Available Program Memory (kB) RAM(KiB)Estimated Sleep Current Draw PIC24FJ64 GA102 Yes 648~10 uA PIC24HJ32 GP202 Yes 322~100 uA

Month August September October November Research Hardware design Programming Prototyping Testing Final Prototype

Hardware Design Ordered Parts -Microcontroller -SD card socket Prototype construction -SD card socket installed -Power supply Began software development -Successfully written data to an SD card

Finish software development -SD card initialization routines -FAT16, FAT32 file system management -input configuration -buffering scheme

Problem SD card overhead is burdensome Solution S-Drive will handle overhead Design Constraints packaging, current draw, etc. Technical Tradeoffs File Allowance (1, 2, or more) Microcontrollers (PIC24H vs. PIC24F)

[7] Microchip, “PIC24F Family Reference Manual, Sect. 21 UART,” Microchip Technology Inc., January 26, [Online]. Available: [Accessed September 14, 2010]. [8] Microchip, “PIC24F Family Reference Manual, Sect. 23 Serial Peripheral Interface (SPI),” Microchip Technology Inc., March 22, [Online]. Available: [Accessed September 14, 2010]. [9] STEC, “SLDSxxxBS(I)U Data Sheet,” STEC Inc., March [Online]. Available: inc.com/downloads/flash_datasheets/SLSDxxxB_I_U pdf. [Accessed September 14, 2010]. inc.com/downloads/flash_datasheets/SLSDxxxB_I_U pdf [10] Sparkfun Electronics, “Logomatic v2 Serial SD Datalogger,” On-Line Store,2010.[Online].Available: p?products_id=8627. [Accessed:September 14, 2010]. [11] C-ONE Technology Corp., “Wide Temperature Industrial SD Card Product Specification,” May [Online]. Available: [Accessed: September 14, 2010].