Dwight K. Elvey wrote: XIII or XIIIA? In either case, yes. XIII is two Banks of 16Kx8 each, called Bank A and Bank B, and can be configured to place each Bank at any 16KB boundary in the 64KB address space. It has four groups of 8 DIP switches, S1 through S4. S1 sets the I/O port address for Bank A. Output a 0 to this port, the bank is disabled. Output a 1, the bank is enabled. You can read it too; 0 means disabled and 1 means enabled. S1-1 sets address bit 0, S1-2 sets address bit 1, ... S1-8 sets address bit 7. On = 1, Off = 0. S2 sets the I/O port address for Bank B. Same scheme. S3 positions 1-4 are not used. S3 positions 5 and 6 set whether to enable or disable Bank B on power-up: set S3-5 to 1 and S3-6 to 0 to disable Bank B, or set S3-5 to 0 and S3-6 to 1 to enable Bank B. S3 positions 7 and 8 work like 5 and 6, but for Bank A. S4 positions 1-3 and 7 control Bank A. S4-1, if on, disables Bank A entirely. S4-2 and -3 set the address bus line 14 and 15 values to match for Bank A (on is 0 and off is 1). And S4-7, if on, enables PHANTOM on Bank A. S4 positions 4-6 and 8 control Bank B in much the same ways. XIIIA is a single 32Kx8 block that can be located at any 4KB boundary. It has four groups of 8 DIP switches, S1 through S4. S2 positions 1 and 2 are used to enable or disable the board at power-up. Set S2-1 on and S2-2 off to enable the board at power-up, or S2-1 off and S2-2 on to disable the board at power-up. S2 position 3 controls how the board responds to PHANTOM*. S2-3 set on will make the board disable itself in response to PHANTOM*. S2 position 4 grounds MWRITE (bus pin 68) and makes the board respond to pWR* (bus pin 77). S2 positions 5-8 set the starting address at which the board appears in the 64KB address space. S2-5 sets the value to match for address line 15, S2-6 for line 14, ..., S2-8 for line 12. S1 lets you disable 4K blocks within the 32K block. S1-1 for block 7, S1-2 for block 6, ..., S1-8 for block 0. Off is enabled, on is disabled. S4 sets the I/O port address for the board. S4-1 is address bit 7, ..., S4-8 is address bit 0. Off is 0, on is 1. S3 sets the data bits in the I/O port to which the board responds. S3-1 is bit 7, ..., S3-8 is bit 0. Off is 0, on is 1. Those bits switched on must all be set to 0 by the output operation to disable the board. Any of the bits switched on may be set to 1 to enable the board. -Frank McConnell