CP reads the hardware configuration by Store-SubChannel-ID. That ID must map to a device number. Using SubChannel-ID, CP can issue I/O to get device information like device type. Using device type, CP can decide what to do with the device. DASD: read its label. Terminal: write the logon logo. Etc.
But it all starts with the hardware being properly defined. IOCDS. Gotta have it. Richard Corak
It's been quite a while since I worked at that level but I didn't (don't) think that CP is going to be able to sense anything that isn't defined in the active IOCDS. It seems to me that was why I used to have to give a tape to the CE to load a basic IOCDS that would be enough to start with. I hope I'm wrong. Jim
