GPIO5 on STR912FAW44X6

[nik]

Posted on February 21, 2008 at 14:13

GPIO5 on STR912FAW44X6

[nik]

Posted on May 17, 2011 at 09:50

Hi folks,

is this a bug or a feature?: as soon as GPIO5 is powered up (recover from reset and clock), pins 0 throught 7 except for 3 are in ''high''. Thus they cannot be used as inputs. It does not make a difference to set clock manually or by startup file. Behaviour is the same. I urgently need to use the pins as inputs. Any help is welcome! Keil uVision3 with MCBSTR9 is used. Cheers Nik

[amira1]

Posted on May 17, 2011 at 09:50

Hello Liqnik,

I tried the external interrupt library example for each input pin from 5.0 to 5.7 under MCB STR9 board and for the two levels rising and falling edge and I found that it's working. Please try to verify if you have something wrong in your code. Best regards, mirou.

[nik]

Posted on May 17, 2011 at 09:50

Hi Mirou,

thanks for your quick response. It seems that it is related to the board from Keil. May be they have something connected to the pins internally. Are you also using the Keil MCBSTR9 with uVision3? If so, try this: 1) create a new project 2) include the startup file for STR912FW44 3) include a c-file: int main (void) { while (1); return 0; } 4) edit the startup file with the wizard: enable the clocks for GPIO0-7 enable reset configuration put GPIO0-7 to ''Not in reset'' 5) save the file and compile 6) load and debug 7) check the status of the GPIOs: they are all messed up, some high, some low... Something else I find quite confusing: when applying a logical 1 to the pins of some ports they remain 1 even when the signal is removed. :( I am far from being an expert, but since that minimal prog causes the same weird behaviour as soon as the startup file enables the ports, it must be something with either the board or the startup file. Correct me, if I am wrong. I am willing to learn. ;) Cheers Nik