The Softcard III Installation manual recommends on page 83 that a user allocate 3200 SOS BLOCKS into two CP/M volumes (each 1600 blocks) when setting up ProFile. This will give the user approximately 792K in each CP/M volume. These blocks are on the ProFile and in no way effect the size of the transient program area (TPA). The TPA is fixed by the implementor (Apple) and cannot be changed. The size of the TPA is defined as the memory range from 0100H to the bottom of the BDOS (0CC00H), which works out to 50.75K (51,960 Bytes). Note that the TPA includes the area of memory used by the CCP (2K). Application programs may overwrite the CCP and use the 2K of memory, but must exit back to the CP/M system via a Warm Boot (which reloads the CCP). Remember that SOS device drivers reside outside of the CP/M environment and therefore have no effect on the size of CP/M. CP/M takes up 56K in the Apple III because of the amount of BIOS code required to interface to device drivers. Use 2060 blocks for each CP/M volume on the ProFile. This works out to 1 Meg of user space (exlcuding directory) for each volume. We highly recommend that you use the updated version of the CP/M Boot & BIOS code, version 2.21.