Parallel library for Due External Memory Bus/Static Memory Controller

Hardware Arduino Due
6

Here are most of the SMC pins and how they are connected. I left out the NAND flash stuff and didn't double check for accuracy...

Address Bus:

Function Chip Pin Arduino Pin
A0 PC21 PWM9
A1 PC22 PWM8
A2 PC23 PWM7
A3 PC24 PWM6
A4 PC25 PWM5
A5 PC26 PWM4
A6 PC27 N/C
A7 PC28 PWM3
A8 PC29 PWM10
A9 PC30 RX LED
A10 PD0 PIN 25
A11 PD1 PIN 26
A12 PD2 PIN 27
A13 PD3 PIN 28
A14 PD4 TXD0
A15 PD5 RXD0
A16 PD6 PIN 29
A17 PD7 PWM11
A18 PA25 MISO
A19 PA26 MOSI
A20 PA27/PA18 SPCK/SCL1
A21 PD8 PWM12
A22 PD9 PIN 30

Here is the data bus:

Function Chip Pin Arduino Pin
D0 PC2 PIN 34
D1 PC3 PIN 35
D2 PC4 PIN 36
D3 PC5 PIN 37
D4 PC6 PIN 38
D5 PC7 PIN 39
D6 PC8 PIN 40
D7 PC9 PIN 41
D8 PC10 N/C
D9 PC11 N/C
D10 PC12 PIN 51
D11 PC13 PIN 50
D12 PC14 PIN 49
D13 PC15 PIN 48
D14 PC16 PIN 47
D15 PC17 PIN 46

And the control signals:

Function Chip Pin Arduino Pin
NRD PA29(also tied to PC26 on PCB, which is A5) SS1/PWM4
NWE PC18 PIN 45
NCS0 PA6 AD4
NCS1 PA7 PIN 31
NCS2 PB24 N/C
NCS3 PB27 PWM13

There isn't too much you can do with the A5/NRD problem in software since the two pins are wired together on the PCB (I am not sure why those pins are wired together...) If you were careful, you could cut the trace on the bottom side of the board...

I can pretty easily add all the pins to the library and let the user sort out any conflicts.