Hi.
I had to my Olimex LPC-P2138 a matrix keypad 4x4, connected on port1 (Rows on
P1.16 to P1.19, and Columns on P1.20 to P1.23), and it works fine !
Now, i want to connect this keypad on port0, for example rows on P0.3 to P0.6,
and columns on P0.7 to P0.10, and it doesn't work... the keypad have a
strange behaviour...
So it's a normal thing, i can't use it on port0 ? (be indulgent,
i'm a newbie on arm development...)
Regards
Alek
Matrix keypad on port0 not work ?
Started by ●September 17, 2010
Reply by ●October 1, 20102010-10-01
Hi and sorry for my late reply... So all my keypad concerned pins are selected
as GPIO, not on others functions, and assign 4 pins on output, and 4 on input,
like:
GPIO0_IODIR := GPIO0_IODIR or (1 shl 4); -> for pin 4 ouput
...
GPIO0_IODIR := GPIO0_IODIR and not (1 shl 8); -> for pin 8 output
Thanxs
Regards
> Read Chapter 7 "Pin Connect Block" Section 4 "Register Description" in the NXP User Manual UM10139. It might be that those pins are already being used for some other purpose on your board.
>
> Regards,
> Chris Burrows
> CFB Software
> http://www.cfbsoftware.com
>
GPIO0_IODIR := GPIO0_IODIR or (1 shl 4); -> for pin 4 ouput
...
GPIO0_IODIR := GPIO0_IODIR and not (1 shl 8); -> for pin 8 output
Thanxs
Regards
> Read Chapter 7 "Pin Connect Block" Section 4 "Register Description" in the NXP User Manual UM10139. It might be that those pins are already being used for some other purpose on your board.
>
> Regards,
> Chris Burrows
> CFB Software
> http://www.cfbsoftware.com
>
