Disk I/O Support

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)

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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.)

The following system calls are provided to allow user programs to do disk I/O:

.DSKRD

Disk read. System call to read blocks from a disk into memory.

 

 

.DSKWR

Disk write. System call to write blocks from memory onto a disk.

 

 

.DSKCFIG

Disk configure. This function allows you to change the configuration of

 

the specified device.

 

 

.DSKFMT

Disk format. This function allows you to send a format command to the

 

specified device.

 

 

.DSKCTRL

Disk control. This function is used to implement any special device

 

control functions that cannot be accommodated easily with any of the

 

other disk functions.

 

 

Refer to the Debugging Package for Motorola 68K CISC CPUs User’s Manual for information on using these and other system calls.

MVME162IG/D2

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Motorola MVME162 Disk I/O via 162Bug System Calls, IOC I/O Control, BO Bootstrap Operating System, BH Bootstrap and Halt