EMBEDDED SD/MMC CARD INTERFACE WITH FAT32 FILESYSTEM SUPPORT
IMAGES of the test hardware:
All images (large sized)
are available from the downloads section.
The phoenix
The board has an atmega16 microcontroller, an RS232 level translator, an on board voltage regulator (LM 317 set to generate 5V), an external 8MHz crystal for precise clocking, ISP programming connector and headers for all I/O pins.
The micro SD adapter has the exact form factor of a standard SD card.
MICROSD
ADAPTER WITH A 7 PIN CONNECTOR SOLDERED DIRECTLY TO THE CONTACTS. THIS MUST BE
DONE CAREFULLY OR THE HEAT WILL DAMAGE THE PLASTIC BODY.
The 7 pin connector comprises DOUT, DIN, SCK, \CS, VCC, VSS and VSS lines. (not in order)
Back
side of the add on board. The add-on board has 8 pins to fit into the 8 pin
header for PORTB on the main board. Of this, only MOSI, MISO, SCK and SS are
connected; the other 4 lines are unused. Power for the add on board is sourced
from a separate 2 pin connector that mates with a 5V connector on the main
board. The potential divider resistances are also visible.
Front
side of the add-on board showing the regulator that generated 3.3V supply for
the card, and the power supply cable.
Add
on board attached to the main board. Power and RS232 connectors are visible on
the left side of the board.