Why after an download of a PG5 2.2.230 project to the PCD, where BACnet revision 14 is used, the application program on the PCD doesn’t work correctly and have a randomly unexpected/unwanted functionality?

FAQ #102013

Error description:
Due to an error on the PG5 2.2.230 BACnet compiler, PCD resource addresses changes (Reg-ister/Flags/DB’s/Text address change of existing symbols) on existing PG5 projects are not detected from the PG5 BACnet compiler and therefore the changed PCD resource addresses are not taken in account in the PCD after the download of the modified program.

Detail information:
The PG5 BACnet compiler generate a checksum (CRC) over all PCD resources. This CRC is checked by the PCD firmware after the program download or the restart of the PCD to detect if the BACnet configuration has changed.
If the CRC has changed, then the PCD firmware forces the BACnet stack to reload the BACnet configuration in the PCD.
If the CRC has not changed then BACnet configuration is not loaded again in to the BACnet stack.
The error consists in the fact, that on PG5 2.2.230, the BACnet compiler doesn’t uses the PCD resource address for the CRC calculation and therefore a PCD resource address change of already existing PG5 resources doesn’t generate a different CRC.

The change of PCD resource addresses (Register/Flags/DB’s/Text addresses change of exist-ing symbols) could occur at any time to all, from PG5 automatically allocated PCD resources, if an existing PG5 2.2.230 project is modified or if the user changes manually allocated address of existing PG5 resources.

Error behavior:
The above described error lead to the situation that after the download of a modified PG5 ap-plication to the PCD, the BACnet Stack on the PCD uses still the old PCD resource address of PG5 resources instead of the new one.
This error could invoke a malfunction of the application program running on the PCD for PCD resources which are used/handled from the BACnet stack.

This behaviour could result to the situation that the application program on the PCD doesn’t work correctly and could create/provoke a randomly unexpected/unwanted functionality of the PCD application program.

Error correction:
The error will be fixed in PG5 2.2.234 or newer PG5 2.2 versions.
PG5 2.2.234 or newer should be available at the beginning of 2018.

Workaround for PG5 2.2.230:
The recalculation of the CRC can be forced by the user, if after each build something is changed manually in the BACnet configurator.
For example, a text string for the ‘Description’ or the ‘Location’ item on the BACnet configurator where the name could added with an underline ‘_’.
The new calculated CRC will then force the BACnet stack to load the new configuration.

Example to force the recalculation of the CRC:
Old Value for Location was ‘Murten’                  New Value for Location is ‘Murten_’