DS11 Multiple Line Synchronous Interface
The DS11 Multiple Line Synchronous Interface was an early synchronous serial line interface for the UNIBUS; it could handle up to 16 lines. It used programmed I/O (with separate receive and transmit interrupts) to transfer data; it could operate in either half-duplex or full-duplex mode.
It provided an EIA RS-232 interface to Bell 200 series modems (such as the model 201, and equivalents), and also connect to Bell 300 series modems, such as the model 303. Character lengths of 6, 8 and 12 bits were supported, and could be configured by software.
It consisted of a master line scanner, and up to four adapters, each of which could handle up to four lines; each line had a separate quad M7110 Line Control Module. It used an M105 Address Selector to set its bus address. Physically, it is a large quad-height backplane, mounted in a 19" cabinet such as an H950, along with an DEC indicator panel.
Registers
| Register | Abbreviation | Address |
|---|---|---|
| Receiver Status Register | RxCSR | 775xx0 |
| Receiver Data Buffer Register | RxDBUF | 775xx2 |
| Transmitter Status Register | TxCSR | 775xx4 |
| Transmitter Data Buffer Register | TxDBUF | 775xx6 |
Line addresses:
- Line 0: 775400-775406
- ...
- Line 15: 775570-775576
See also
Further reading
- DS11 Multiple Line Synchronous Interface Maintenance Manual (DEC-00-DS11-DB; not available online, but in fiche)
External links
- DECsystem-10 System Reference Manual - documents the DS11 registers in Appendix C (pp. 370-371 of the PDF)
- M7110
