Solaris 7 (Intel Platform Edition) Device Configuration Guide

Select an adapter model ending in "C" as the primary controller.
Choose an I/O address for the primary controller that precedes the secondary controller in "Supported Settings"; for example, use an I/O address of 0x234 for the primary controller, and make sure the secondary controller uses either 0x130 or 0x134.
Disable the BIOS on the secondary controller.
Wide-mode EISA adapters can support targets greater than 7 if the proper entries are added to the system configuration files: /kernel/drv/sd.conf (for disk) and /kernel/drv/st.conf (for tape).