The SMV SmpSynch field is defined to operate in different way in IEC 61850-9-2 Ed 1 and Ed 2.1 standard versions. By default the behavior of this field follows the IEC 61850 edition that is selected in PCM600 tool.
To override the SmpSynch behavior, for backward compatibility reasons, parameter "Smv SmpSynch" format can be used. In Ed 1 mode the SmpSynch values are FALSE/TRUE and in Ed 2.1 mode SmpSynch values are: 0=none, 1=local, 2=global. The relay SMV receiver decoder can accept both however properly. However backwards compatibility might be needed for example for older 3rd party devices.