Difference between revisions of "RK11 disk controller"

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(Added disk-''n'' bootstrap)
Line 23: Line 23:
 
|1014||105710||TSTB (r0)                ||Test byte at 177404
 
|1014||105710||TSTB (r0)                ||Test byte at 177404
 
|-
 
|-
|1016||100376||JMP *-1                  ||Jump backward if positive
+
|1016||100376||BPL *-1                  ||Jump backward if positive
 
|-
 
|-
 
|1020||005007||CLR PC                  ||Jump to zero
 
|1020||005007||CLR PC                  ||Jump to zero

Revision as of 02:24, 17 May 2007

The RK11 is the UNIBUS controller for the RK05 moving-head magnetic disk drive.

PDP-11 bootstraps

Disk 0

I know the octal data is correct, but I'm not sure about the mnemonics and the description.

Address Data Mnemonic Description
1000 012700 MOV #177406,r0 Move the top of the address of the controller into r0
1002 177406 (constant)
1004 012710 MOV #177400,(r0) Move 177400 into 177406
1006 177400 (constant)
1010 012740 MOV #000005,-(r0) Move 5 into 177404
1012 000005 (constant)
1014 105710 TSTB (r0) Test byte at 177404
1016 100376 BPL *-1 Jump backward if positive
1020 005007 CLR PC Jump to zero

Disk n

Address Data Mnemonic Description
1000 012700 MOV #177406, R0
1002 177406 (constant)
1004 012760 MOV xxxxxx, 000004(R0)
1006 xxxxxx (disk ID number)
1010 000004 (index)
1012 012700 MOV #177406, R0
1014 177406 (constant)
1016 012710 MOV #177400, (R0)
1020 177400 (constant)
1022 012740 MOV #000005, -(R0)
1024 000005 (constant)
1026 105710 TSTB (R0)
1030 100376 BPL *-1
1032 005007 CLR PC