[En-Nut-Discussion] Panel Expansion and other available GPIO pins

[Peter Gaskell]

We have ordered a new Ethernut 3 board and it should be on its way.   
I'm trying to compile a list of the pins on the Expansion we can use  
hoping to find 25 useable I/O pins to interface with a parallel bus  
that is used by several boards that are already designed and tested.

The bus has 8 Address lines and 16 Data lines and one more for  
Address/Data Strobe.  I'm looking at the Expansion port pin list and  
i see the 8 configurable data bus bits and i wonder if they would be  
easily useable for my Address Bus.

i'm also trying to find 17 other lines without reprogramming the CPLD  
but it looks like i might, the lines i think i can use are pins: 
40-42,44-54,58,60. which is only 16, i am not sure about using 59,61  
and 62 because of Note 8 on reprograming the CPLD, and i am pretty  
sure i cannot use 39,43,55,56,57 because the are used for other  
things or require reprogramming the CPLD.

Am I correct? Has anyone used the Panel lines for expansion? Am i  
going to find other pitfalls with my plan to get 17 lines? should i  
skip my worrying and get a couple I2C I/O port expanders?  We'd like  
to make this run as fast as possible with the Ethernut 3 so a  
parallel interface is preferable.

also has anyone done an install of the ARM-GCC stuff for OSX or  
linux?  i have yet to see a description of all the steps needed to  
get it up and running.


thanks for putting up with all my predesign questions

-peter