By default, when you create a new NI-Digital Pattern instrument in the pin map file, the NI TestStand 2019 Semiconductor Module (TSM) and later set the group attribute to Digital so that all newly created NI-Digital Pattern instruments belong to the same group. TSM creates a single session for each group of NI-Digital Pattern instruments in the pin map file. TSM 2017 and earlier do not automatically group NI-Digital Pattern instruments together in pin map files. Use the Pin Map Editor to modify existing pin map files to change the value of the Group option for each instrument to assign the instrument to the same group.