1. Provide 2x 20x2 40 pin
same as Pi, one use 40pin GPIO cable connect to Pi
one 20x2 40pin for GPIO pin extra access.
2. Provide extra
i2c pin and spi pin for easy connect device
3.
Provide 128 GPIO
status blue LED
4 Provide
each 23017 Address select A0,A1,A2
can rearrange
23017 location by your
order
5. U2 ,U3 ,U4, U5 ,U6 ,U7,U8 ,U9 23017 Port A,B
6. Each GPIO pin out 2X10 ,
Bank B(1-10)
GPIO (0,1,2,3,4,5,6,7,GND, INTB)
Bank A(1-10) GPIO (0,1,2,3,4,5,6,7,GND, INTA)