RK11 disk controller
From Computer History Wiki
The RK11 is the UNIBUS controller for the RK05 moving-head magnetic disk drive.
Contents
- 1 Physical implementation
- 2 Device registers
- 2.1 777400: Drive Status Register (RKDS)
- 2.2 777402: Error Register (RKER)
- 2.3 777404: Control Status Register (RKCS)
- 2.4 777406: Word Count Register (RKWC)
- 2.5 777410: Current Bus Address Register (RKBA)
- 2.6 777412: Disk Address Register (RKDA)
- 2.7 777414: Maintenance Register (RKMR)
- 2.8 777416: Data Buffer Register (RKDB)
- 3 PDP-11 bootstraps
- 4 Documentation
Physical implementation
Todo.
Device registers
| Register | Abbreviation | Address |
|---|---|---|
| Drive Status Register | RKDS | 777400 |
| Error Register | RKER | 777402 |
| Control Status Register | RKCS | 777404 |
| Word Count Register | RKWC | 777406 |
| Current Bus Address Register | RKBA | 777410 |
| Disk Address Register | RKDA | 777412 |
| Maintenance Register | RKMR | 777414 |
| Data Buffer Register | RKDB | 777416 |
777400: Drive Status Register (RKDS)
| Drive Ident. | DPL | HDEN | DRU | SIN | SOK | DRY | ARDY | WPS | SC=CA | Sector Counter | |||||
| 15 14 13 | 12 | 11 | 10 | 09 | 08 | 07 | 06 | 05 | 04 | 03 02 01 00 | |||||
777402: Error Register (RKER)
| DRE | OVR | WLO | SKE | PGE | NXM | DLT | RTE | NXD | NXC | NXS | CSE | WCE | |||
| 15 | 14 | 13 | 12 | 11 | 10 | 09 | 08 | 07 | 06 | 05 | 04 03 02 | 01 | 00 | ||
777404: Control Status Register (RKCS)
| ERR | H.E. | SCP | M | IBA | FMT | R/WA | SSE | RDY | IDE | EX. MEM | FUNCTION | GO | |||
| 15 | 14 | 13 | 12 | 11 | 10 | 09 | 08 | 07 | 06 | 05 04 | 03 02 01 | 00 | |||
777406: Word Count Register (RKWC)
| WC15 <---> WC00 | |||||||||||||||
| 15 | 14 | 13 | 12 | 11 | 10 | 09 | 08 | 07 | 06 | 05 | 04 | 03 | 02 | 01 | 00 |
777410: Current Bus Address Register (RKBA)
| BA15 <---> BA00 | |||||||||||||||
| 15 | 14 | 13 | 12 | 11 | 10 | 09 | 08 | 07 | 06 | 05 | 04 | 03 | 02 | 01 | 00 |
777412: Disk Address Register (RKDA)
| DRIVE SELECT | CYLINDER ADDRESS | SUR | SECTOR ADDRESS | ||||||||||||
| 15 | 14 | 13 | 12 | 11 | 10 | 09 | 08 | 07 | 06 | 05 | 04 | 03 | 02 | 01 | 00 |
777414: Maintenance Register (RKMR)
| M RCP |
M RDP |
M SPS |
M ADA |
M LAI |
M DRY MR/W/S |
MAINTENANCE SECTOR COUNTER | |||||||||
| 15 | 14 | 13 | 12 | 11 | 10 | 09 | 08 | 07 | 06 | 05 | 04 | 03 | 02 | 01 | 00 |
777416: Data Buffer Register (RKDB)
| DB15 <---> DB00 | |||||||||||||||
| 15 | 14 | 13 | 12 | 11 | 10 | 09 | 08 | 07 | 06 | 05 | 04 | 03 | 02 | 01 | 00 |
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 #5,-(r0) | Move 5 into 177404 |
| 1012 | 000005 | (constant) | |
| 1014 | 105710 | TSTB (R0) | Test byte at 177404 |
| 1016 | 100376 | BPL 1014 | Jump backward if positive |
| 1020 | 005007 | CLR PC | Jump to zero |
Disk n
This bootstrap will boot from any disk in a daisy-chained multi-drive configuration. Memory location octal 1006 contains the unit number, as follows:
| Value | Unit |
|---|---|
| 020000 | Unit 1 |
| 040000 | Unit 2 |
| 060000 | Unit 3 |
| 100000 | Unit 4 |
| 120000 | Unit 5 |
| 140000 | Unit 6 |
| 160000 | Unit 7 |
| Address | Data | Mnemonic | Description |
|---|---|---|---|
| 1000 | 012700 | MOV #177406, R0 | Store the address of the Word Count register in r0 |
| 1002 | 177406 | (constant) | (Which is 177406) |
| 1004 | 012760 | MOV xxxxxx, 000004(R0) | Store the disk ID number in the Disk Address register |
| 1006 | xxxxxx | (disk ID number) | The disk number goes here. |
| 1010 | 000004 | (index) | |
| 1012 | 012700 | MOV #177406, R0 | Store the addresss of the Word Count register in r0 |
| 1014 | 177406 | (constant) | (Which is 177406) |
| 1016 | 012710 | MOV #177400, (R0) | Store 177400 into the Word Count register, |
| 1020 | 177400 | (constant) | meaning that octal 400 words are to be read. |
| 1022 | 012740 | MOV #000005, -(R0) | Store 5 into the Control Status register |
| 1024 | 000005 | (constant) | selecting the function "read" with 4, and "go" with 1 |
| 1026 | 105710 | TSTB (R0) | Test the Control Status Register (upper) byte |
| 1030 | 100376 | BPL *-1 | Repeat if it's positive, that is Control Ready is cleared |
| 1032 | 005007 | CLR PC | If not, clear the Program Counter (essentially, jump to 0) |
