An expansion chassis was released, providing an additional 64 kB of paged memory. Since the Z80 has a 16-bit address bus, it can only address 64 kB of memory at a time. The paged memory system in the expansion chassis used bank switching to allow the NewBrain to take advantage of several 64 kB modules. The expansion module included a parallel printer port and two hardware based serial ports and an expansion bus to connect further modules such as the 8 and 16 way serial modules under development. The expansion module included Series 2 software, replacing those in the processor module as well as software for the new devices.