You can use the CPU Affinity step type to specify the CPU affinity mask of a process or thread. Because 32-bit Microsoft Windows uses a 32-bit CPU affinity mask, and 64-bit Windows uses a 64-bit mask, the mask behaves as a pointer-sized integer. 32-bit TestStand expects the affinity mask to be a TestStand Number data type with the default (double) representation. 64-bit TestStand expects the affinity mask to be a Number data type with the 64-bit unsigned integer representation.

If a sequence needs to support only one architecture, use the representation that matches the required architecture. If the sequence must support the 32-bit architecture and the 64-bit architecture, use bitness-conditional code in the mask expression. For example, to enable all CPUs, use the following expression:

RunState.Engine.Is64Bit? -1ui64 : -1

where -1 indicates to set all bits and therefore use all CPUs.