virtual CPU Virtual central processing unit (CPU) that executes the instruction codes of a digital organism's genome. It can take two values: 'default' (virtual CPU running on the default hardware: it consists of a memory space with four heads pointing to specific locations in that memory, three registers, two stacks, and input and output buffers) and 'transsmt' (virtual CPU running on the Transsmt hardware: it consists of a memory space with four heads pointing to specific locations in that memory, four stacks, and input and output buffers). default transsmt digital organism