This a circuit that utilizes the FTDI chip in order to make the Arduino communicate with the USB. The memory card pins are like such: (Thanks to Shendo's hardware)

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 1 2 3 4 5 6 7 8

1. DATA - Pin 12 on Arduino

2. CMND - Pin 11 on Arduino

3. 7.6V - External 7.6V power (only required for 3rd party cards and knockoffs)

4. GND - GND Pin on Arduino

5. PIN D3 Always High!

6. ATT - Pin 10 on Arduino

7. CLK - Pin 13 on Arduino

8. ACK - Pin 2 on Arduino

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