[Lcdproc] 4bit-HD44780 and keymatrix...

[Thorsten Godau]

Hi all,

as described in a thread above, i am using a EA DIP204-4 (HD44780->KS0073)
connected the "4bit"-way to the parallel port.
As i undestood the documentation, the other signals, that are not used
for display control can be used for a keymatrix and defined and enabled
as per an entry "keymatrix_X_Y" in the configuration file.

My keymatrix is the following:

  +5V ----------+---------+--------+---------+
                |         |        |         |
               22k       22k      22k       22k
                |         |        |         |
   Y7 -|<|--+---------+--------+---------+   |
            |   |     |   |    |   |     |   |
            o   |     o   |    o   |     o   |
          S1 \  |   S2 \  |  S3 \  |   S4 \  |
            o   |     o   |    o   |     o   |
            |   |     |   |    |   |     |   |
            +---+     +---+    +---+     +---+
                |         |        |         |
                |         |        |         |
   Y8 -|<|--+------------------+---------+   |
            |   |         |    |   |     |   |
            o   |         |    o   |     o   |
          S5 \  |         |  S6 \  |   S7 \  |
            o   |         |    o   |     o   |
            |   |         |    |   |     |   |
            +---+         |    +---+     +---+
                |         |        |         |
   X1 ----------+         |        |         |
                          |        |         |
   X2 --------------------+        |         |
                                   |         |
   X3 -----------------------------+         |
                                             |
   X4 ---------------------------------------+ 

After being not very successful getting my LCD to work with LCDd,
i tested the function of the keys in debug mode.

Unfortunately S1/S5, S3/S6 and S4/S7 are delivering the same keycode
(letter) if being pressed.
So for me it seems, that the Y-lines are not really toggling from high
to low and vice versa round robin to get the scanning-effect.
They seem both to be statically low.

Can anyone confirm that behaviour?

BTW: Is it possible to have the display controlled e.g. with the I2C
connection type and the keypad active on the parallel port?
What are the correct configuration paramteres for that?

Thanks in advance.

Cheers, Thorsten