PDM Keypad sharing

[SDR-Engineering]

Hi, I'm currently working on a car with a double PDM setup and two keypads. I need to add a third keypad which replaces some of the direct inputs on PDM2. Unfortunately I have insufficient space within the CAN communications to forward all buttons from PDM1 to PDM2. From this topic I understand that it is possible to read the key presses from two PDM's (viewtopic.php?f=17&t=3445). Obviously the leds and brightness can only be controlled from one PDM (in this case PDM1).

How should I configure the keypad on PDM2 to read the key presses from the keypads configured on PDM1 without sending any data to the keypad (and causing erratic behavior)?

[NathanB]

Provided you have one of the PDM's setup to receive/control the functions of the keypad (ie. handle wake up and LED control) all you need to do is setup up the appropriate receive addresses to receive the keypad button presses - there is no need to transmit them out of the on PDM to the other - that is counter productive to the purpose of CAN.

You will just need to set up the can receives for the button in the second PDM:

Keypad button receive.jpg (22.98 KiB) Viewed 6510 times