In some products for which I have written firmware, I use the last six digits of the serial number to generate the initial Device ID. In other products, I have used the DIP switch to generate the Device ID until the Device ID is written (via Object_Identifier property of the Device object). A random number generated Device ID might work as well.
There is a proposal to add new BACnet services to assign Device ID (and optionally MAC), but it is not standard yet.
In the discussion for Zero Config (Auto MAC) of MS/TP which has been out for public review, there has been some discussion about adding a specification for Auto Baud, which basically uses a number of valid packets per second to determine a valid baud rate, and also uses a special blast packet for a periiod of time to get all devices to reset and seek a new baud rate. This is not standard yet.
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A collision in Device ID might always occur on a job site, even for devices with a configured Device ID.
I suppose a Device that uses a random Device ID, upon startup, could request Who-Is to the Device ID it wants to use, and if it hears the I-Am, it could choose another random Device ID.
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Hi,
1-I am using the your port of stm32f10x, but on many devices connected using MS/TP to an automation server.
some comercial devices set there instance id automatically, how can I add this functionality to the stm32f10x port?
2- can you advise about autobaud in bacnet?
Thanks.
MAC is set using dip-switches, am just asking about instance nuber.
Last edit: mdeeb 2015-12-20
In some products for which I have written firmware, I use the last six digits of the serial number to generate the initial Device ID. In other products, I have used the DIP switch to generate the Device ID until the Device ID is written (via Object_Identifier property of the Device object). A random number generated Device ID might work as well.
There is a proposal to add new BACnet services to assign Device ID (and optionally MAC), but it is not standard yet.
In the discussion for Zero Config (Auto MAC) of MS/TP which has been out for public review, there has been some discussion about adding a specification for Auto Baud, which basically uses a number of valid packets per second to determine a valid baud rate, and also uses a special blast packet for a periiod of time to get all devices to reset and seek a new baud rate. This is not standard yet.
Thanks
I did the random generation for device ID and its working fine
but as masters number increase, a collesion in device ID might occure?
can the master detect this like in automac you wrote?
A collision in Device ID might always occur on a job site, even for devices with a configured Device ID.
I suppose a Device that uses a random Device ID, upon startup, could request Who-Is to the Device ID it wants to use, and if it hears the I-Am, it could choose another random Device ID.