devchan array in modules?

annuello · October 2007

I'm trying to create a devchan array in a module, using a device that is passed to the module rather than declared in it.

MODULE_NAME='my module' (DEV vdvDevice, DEV dvDevice)
DEFINE_DEVICE

DEFINE_VARIABLE
devchan dcChannels[] = {{vdvDevice,1},{vdvDevice,2},{vdvDevice,3},{vdvDevice,4}}

The compiler keeps complaining:"Initializer is not a constant". This seems to be due to vdvDevice being externally declared rather than in the DEFINE_DEVICE section of the module. The compiler works fine if I do the following:

MODULE_NAME='my module' (DEV vdvDevice, DEV dvDevice)
DEFINE_DEVICE
vdvLocalDev = 33001:1:0
DEFINE_VARIABLE
devchan dcChannels[] = {{vdvLocalDev,1},{vdvLocalDev,2},{vdvLocalDev,3},{vdvLocalDev,4}}

However, this does not achieve what I want - namely a devchan array for several channels on the device that is passed into the module. I was hoping for a devchan array solution so that later in my code I can do the following:

channel_event[dcChannels]{
 on:{
  //Do something
 }
 off:{
  //Do something else
 }
}

Any clues appreciated.

Roger McLean
Swinburne University

AMXJeff · October 2007

You can only create a devchan array with a constant dev. Since your passing in the dev into your module, that dev will never be a constant. You can either pass the entire devchan array into your module, or use an integer array inside your module instead of a devchan array.

//OPTION 1
MODULE_NAME='my module' (DEV vdvDevice, DEV dvDevice)
DEFINE_DEVICE

DEFINE_VARIABLES
volatile integer nChannelList[] = 
{
	1,
	2,
	3,
	4
}

DEFINE_EVENT

channel_event[vdvDevice, nChannelList]
{
	on:
	{
		// do something with the code.
	}
}

//OPTION 2
MODULE_NAME='my module' (DEVCHAN dcChannels[], DEV dvDevice)
DEFINE_DEVICE

DEFINE_VARIABLES

DEFINE_EVENT

channel_event[dcChannels]
{
	on:
	{
		// do something with the code.
	}
}

annuello · October 2007

Fair enough. I guess it is possible to dynamically change the device outside of the module. I've never had the need to do such a thing, so I always thought they were constant. Nice to be corrected on that.

I think I will use your first suggestion. It achieves what I was wanting to do.

Thanks,
Roger McLean
Swinburne University

DHawthorne · October 2007

Another possibility is to populate the array in DEFINE_START rather than while initializing. You'll just need to give it a size dimension as big as the maximum size it might grow.

But I prefer the separate device and channel array approach as well. I have found the DEVCHAN structure to be less useful than I thought it would. It's too limited in many cases.

REBUILD_EVENT · October 2007

annuello wrote:

Fair enough. I guess it is possible to dynamically change the device outside of the module. I've never had the need to do such a thing, so I always thought they were constant. Nice to be corrected on that.

I think I will use your first suggestion. It achieves what I was wanting to do.

Thanks,
Roger McLean
Swinburne University

It should be possible to change things dynamically. But read the help about REBUILD_EVENT before doing so.

devchan array in modules?

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