Hey Guys, as in the topic shown, how can I interface the card, target is a hardware based driver to transfer images or clips onto the card, any idea? Kind regard Brian
: Locked by Moderator
This is simply not enough information. To what kind of device you wish to interface the card? Are concerned about the hardware or the software to handle the card? What do you mean by 'hardware based driver'? Surely there needs to be software to access the card's file structure and allocation tables. E.g. to access a card formatted with the FAT32 filesystem you could look into FatFS by Elm Chan, which is available to AVR controllers and the STM32 series of MC. Its probably easy to port to other architectures: http://elm-chan.org/fsw/ff/00index_e.html
First of all, thanks for the quick answer, had some busy days... well back to my question, hardware based driver ... right. the best question is how to interconnect them together (hardware interface) so i can support SD XC, i also decomposed a "Transcend USB 3.0 Super Speed Multi-Card Reader for SD/SDHC/SDXC/MS/CF Cards" and could not find out any clue expect it is broken now XD. Maybe I should describe the project: I/O/Parts: 1x Switch 2x 9V Batterie (Rechargeable) 1x Voltage regulator 9V 1x Comparator 1x Solar-array 4x Capasitor 1x Button 3x LED 1x 4-State Variable Resistor (Analog Signal) (Vcc - 3/4 Vcc - 1/2 Vcc - 1/4 Vcc) 8x8 MEMS Pixl readout:1ms/Pixl (Analog) (64ms/Frame) precision: 8 bit 1x ATMEGA16 1x SD XC Card 1x SD XC Card-slot (not all parts are displayed here!) Self rechargeable device, can store Pictures in different mod. 1. 1 frame Picture 2. 1 sec long Picture mode (average value will be saved) 3. Video Mod 4. not set yet How to operate: The device can/should operate with or without batteries for limited time (sunlight should be provided) When the device use battery charge orange LED will light up. Red LED will light up when batteries are depleted. Green LED light up when Solar-array supports enough power to recharge the device. The different mod. will be realized with the 4-state variable resistor. Button is for activate/ deactivate/relase an action, atm. is the SD XC Part missing and i could need your help to realize it... kind regard Brian
I suggest to have a look at ELM Chans FatFS Project describing how to access volumes, e.g. on SD Cards with small microcontrollers, like the AVR: http://elm-chan.org/fsw_e.html He provides sample code for SD card usage on AVRs, although a lot of ports now exist for different architectures. Hardware is simple, but keep in mind that SD Cards operate at 3,3 volts and will be toasted when using 5 volts. Ginat volumes like 64 GBytes might not work with FAT32, i didn't look into that yet. Found some info here: http://www.ntfs.com/ntfs_vs_fat.htm It seems that 32 GBytes for a volume might be a limit here.