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I have ordered this board a year back.
How it is different from standard development kits ?
This board has SD Card , 4MB RAM & Battery Support circuit. You can see the schematic here.
4MB – RAM
PN18S32 is used as PSRAM
1bit SD Bus
IO15 – MOSI
IO14 – SCK
IO2 – MISO
Battery Power Supply
Wide Range Regulator SY8008B is used. When we run the board using lithium battery, the regulator must operate from 3V – 4.2 V , when it is powered under USB , 5-5.5 Input expected.
http://www.sunnyqi.com/upLoad/product/month_1306/SY8008.pdf
Vout=0.6*(1+R1/R2). = > 0.6*(1+ 453/100) = 0.6*(1+4.53) = 3.318V
SD Card Access:
In this we have SD card Directory listing routine , SD read / write functions.
I have seen people using non standard SD card libraries to Access SD Card. Actually it is lot easier to use the standard library.
The code is self explanatory
Here is the result of the code
You can also get the code at our github Link
You can order the board here … Coming week we have few more articles on the way
