Reading keys via i2c

[Phaedra]

Hi,

I am attaching a GLK19264-7T-1U display to a Javelin Stamp via i2c.
When I try to read keypresses from the integrated keypad via this connection, the manual is very unclear about how to do this.
Does anyone have any examples or hints on how to do this ?

Thank you,


Phaedra

[Raquel]

Hello,

Thanks for your post.

To read key presses from the display, you will need to send an I2C read transaction to the display. First make sure that the Auto Transmit Key Press is OFF.

Press a key on the display and issue a read. The data sent by the display indicates if there are more keys to read by having bit 7 of the data set (this is the same with Poll Key Press command, section 10.4 of the manual)

If there are no more keys to read, or the master is done reading, the master must issue a NAK on the last read, to tell the display that it is done reading.

Let me know if this helps.
Thanks,

[Phaedra]

Hello Raquel,

thanks for your answer.
I figured it out, and it is working. The only thing I had to guess was the value of the ACK / NACK to send, but it seems to be working and I'm happy :-)

Thanks again,

Phaedra