How can MC detects an IO-Module?

[Marbek_Elektronik]

HI,

we habe an optional input-module on CAN-bus.
If this module is not connected to the CAN-Bus, the MC needs to know this.
Is there a easy possibility to check wether the module is connected or not?

Maybe a way to check is to listen to the address 0x180+8*node-ID ?

What do you suggest?

Thanks,
Bernd

[mebib]

I use the Update-Signal from the poewer supply pin of the I/O module. Each time the value is updated, the signal is true. Connect an off-delay and you can detect if the modul is missing.

Regards

[Marbek_Elektronik]

Thanks,

it is an easy and good idea!

[Jpshockster]

Hi guys

I realize this is an old thread but I figured my question fits the topic so here's my question...

I am also wanting to detect if a module is on the Bus, but I am wanting to detect it from the DP700.  i have an MC088 that is configured with an IOX24-120, an OX12-110 a JS6000 and a Radio controller.   I would like for the Display to check for a heartbeat from the MC88, The IOx24, the OX12, the JS600 Joystick and a radio controller.  The Display is to show an active fault if any of the mentioned devices go offline. I have read the +1 IO Module Communications document and just don't see how the tx message from the OX and IOX module is set up.  I set the IOX module to Node/N1 = 2 and The OX module Node/N1 = 3  using CanKing I can see that the IOX module Transmits on 0x190 and the  OX module transmits on 0x198.  Now what info is actually on those messages is what I am trying to figure out?  Maybe i am going about this all wrong, If anyone has any suggestions I am ready to listen   thanks in advance.

[oiltronic]

I have the "master" of the IO module, in your case the MC088, detect the presence of the IO module as Mebib described (or with an input pin hard-wired to +supply, or with the "Configured" signal from the IO module's CAN sub-bus).  Then I have the MC088 send a CAN message to the screen with a bit flag indicating the IO module connection state.  Naturally, if the MC088 communications fails then the IO module state is unknown, but in that case it's irrelevant anyway.  So I make sure my error messages are prioritized correctly.

All programmable CAN nodes broadcast a status message with the first bit flag always set to TRUE.  The receiver software in the screen then simply forces these flags to FALSE after a short timeout.  Just like a regular software watchdog, and really simple.

[Jpshockster]

So I got it to operate as I intended, will be testing to confirm over time but here is what I did...

I setup individual CAN Rx blocks just for communication faults in the display using the Update signal from the CAN Rx block tied into a delay so if the update signal remains false for longer than a time i specify based on the Tx rate of each device a fault is latched until cycle of power. (until I come up with a sufficient reset condition) knowing the following everything is working as expected.

IOX module was transmitting on 0x190
OX module on 0x198
Joystick on 0x0CFDD633
radio controller on 0x96
CAN Switches on 0x18FF1034

If anyone sees an issue I might eventually get please don't hesitate to let me know. 

Thanks