Disk I/O Support
3-17
3
IOT (I/O Teach)
IOT allows you to change any configurable parameters and
attributes of the device. In addition, it allows you to see the
controllers available in the system.
IOC (I/O Control)
IOC allows you to send command packets as defined by the
particular controller directly. IOC can also be used to look at the
resultant device packet after using the IOP command.
BO (Bootstrap Operating System)
BO reads an operating system or control program from the
specified device into memory, and then transfers control to it.
BH (Bootstrap and Halt)
BH reads an operating system or control program from a specified
device into memory, and then returns control to 162Bug. It is used
as a debugging tool.
Disk I/O via 162Bug System Calls
All operations that actually access the disk are done directly or
indirectly by 162Bug TRAP #15 system calls. (The command-level
disk operations provide a convenient way of using these system
calls without writing and executing a program.)