DMV11 Synchronous Controller
The DMV11 Synchronous Controller (more fully, the DMV11 Intelligent Communications Synchronous Line Controller) is a multi-line synchronous serial line interface for the QBUS. It used DMA to transfer data. It could operate in either half-duplex or full-duplex, at baud rates up to 56K bits/second (depending on software and system configuration), and supported both point-point and multi-point operation.
The byte-oriented DDCMP line protocol was supported; a microprocessor is used to implement the protocol.
It was a quad card; Berg headers on the card connected to flat cables which led off to the modem connectors. There were 4 models, the -AP, -BP, and -FP used the M8053 card, and the -CP used the M8064. (Earlier, there were 3 models; the -AA, -AB, and -AC.) They supported the following interface standards:
| Model | Interface |
|---|---|
| -AP | EIA RS-232C/CCITT V.28 |
| -BP | CCITT V.35 |
| -CP | Integral modem |
| -FP | EIA RS-423A/CCITT V.24 |
Registers
| Register | Abbreviation | Address |
|---|---|---|
| Control and Status Register | SEL0 | 16xxx0 |
| Control/Response Code Register | BSEL2 | 16xxx2 |
| Tributary Address | BSEL3 | 16xxx3 |
| Command/Response Register | SEL4 | 16xxx4 |
| Command/Response Register | SEL6 | 16xxx6 |
Addresses are assigned from the floating device address space.
