Received Data Serial Device Definition
Posted: Thu Feb 24, 2011 8:46 am
I'm not sure whether this should be considered a feature request or a bug, but anyway...
The ability to channel received serial data to more than one device may prove beneficial but I'm not sure how. What I've found (i.e. stumbled upon) is that by the setting of this property to ALL in the hardware device setup is essentially creating a "network" of all serial devices and their associated COM ports. The problem (if it is one, and I think it could be) is that unrelated/dissimilar devices (projector, alarm controller, AV receiver..) really have no need to hear from the other devices on the network. For example, the ELK M1 alarm controller streams status messages out its port to the HB server every 30 secs. My other equipment has no need for that info so it either ignores it or worse, responds with a NAK or similar "WTF" type message. This could cause problems with the device's input buffer or the device may actually think it understands the message and try to interpret and act on it. This could cause the device to lock up or freeze. Changing the "Received Data Serial Device Destination" for each serial device hardware interface from the default "ALL" to only the device interested in the data removes the network chatter problem. I think the default during serial hardware device setup should not be ALL but rather prompt for the name/description of a serial device. But maybe I don't understand the value of this property...
The ability to channel received serial data to more than one device may prove beneficial but I'm not sure how. What I've found (i.e. stumbled upon) is that by the setting of this property to ALL in the hardware device setup is essentially creating a "network" of all serial devices and their associated COM ports. The problem (if it is one, and I think it could be) is that unrelated/dissimilar devices (projector, alarm controller, AV receiver..) really have no need to hear from the other devices on the network. For example, the ELK M1 alarm controller streams status messages out its port to the HB server every 30 secs. My other equipment has no need for that info so it either ignores it or worse, responds with a NAK or similar "WTF" type message. This could cause problems with the device's input buffer or the device may actually think it understands the message and try to interpret and act on it. This could cause the device to lock up or freeze. Changing the "Received Data Serial Device Destination" for each serial device hardware interface from the default "ALL" to only the device interested in the data removes the network chatter problem. I think the default during serial hardware device setup should not be ALL but rather prompt for the name/description of a serial device. But maybe I don't understand the value of this property...