
3.2 The Assignment of I/O Address
The plug & play BIOS will assign the proper I/O address to PIO/PISO series card. If there is only one PIO/PISO board, the user can identify the board as card_0. If there are two PIO/PISO boards in the system, the user will be very difficult to identify which board is card_0? The software driver can support 16 boards max. Therefore the user can install 16 boards of PIO/PSIO series in one PC system. How to find the card_0 & card_1?
The simplest way to identify which card is card_0 is to use wSlotBus & wSlotDevice as follows:
1.Remove all 
2.Install one 
3.Remove all 
4.Install one 
5.Repeat (3) & (4) for all PCI_slot?, record all wSlotBus? & wSlotDevice?
The records may be as follows:
PC’s PCI slot  | wSlotBus  | wSlotDevice  | 
Slot_1  | 0  | 0x07  | 
Slot_2  | 0  | 0x08  | 
Slot_3  | 0  | 0x09  | 
Slot_4  | 0  | 0x0A  | 
 | 
  | 
  | 
Slot_5 | 1  | 0x0A | 
Slot_6 | 1  | 0x08 | 
Slot_7 | 1  | 0x09 | 
Slot_8 | 1  | 0x07 | 
The above procedure will record all wSlotBus? & wSlotDevice? in the PC. These values will be mapped to this PC’s physical slot. This mapping will not be changed for any 
Step 1: Record all wSlotBus? & wSlotDevice?
Step2: Use PIO_GetConfigAddressSpace(…) to get the specified card’s wSlotBus & wSlotDevice
Step3: The user can identify the specified