DZ11 asynchronous serial line interface
The DZ11 was a UNIBUS 8 port asynchronous serial line mux card for DEC computers. It used programmed I/O, and thus could present a considerable load on the CPU when running a high speed line, using interrupts. A 64-entry FIFO buffer silo was provided on the input side.
Both EIA and 20mA physical layers were supported; the EIA model could operate with full-duplex modems. It provided program-set baud rates (up to 9600 baud), but not split speed. Break could be detected or generated on each line.
A single EIA DZ11 with an EIA-specific 16-line distribution panel was denominated as a DZ11-A; an EIA board by itself was a DZ11-B, and a distribution panel with two boards is a DZ11-E. Similarly, a single 20mA DZ11 with a 20mA-specific 16-line distribution panel was denominated as a DZ11-C, the 20mA board by itself was a DZ11-D, and a distribution panel with two boards is a DZ11-F.
On the M7819, a flat cable led from a Berg connector on the card via a static filter to an H317-E EIA distribution panel (for ID purposes, the DEC part number for the PCB of the H317-E is 54-11928). The H317-E held 16 DB25 male connectors (DB-25P) wired as DTEs, enough for two DZ11 cards.
Accessories for the M7819 EIA version are:
- BC05W-15 50 conductor signal cable
- H7004C Static Filter
- BC06L-0J 50 conductor signal cable
- H317-E EIA distribution panel
- Cable Box assembly
- H325 test connector (single line)
- H3271 staggered test connector
The later H3006 distribution panel for the EIA version was part of DEC's modular back-panel system.
For the 20mA M7814, substitute the:
- BC08S-15 40 conductor signal cable
- H7004B Static Filter
- BC06K-0J 40 conductor signal cable
- H317-F 20mA distribution panel
- H3190 staggered test connector.
|Control and Status Register||CSR||760100|
|Receiver Buffer Register*||RBUF||760102|
|Line Parameter Register*||LPR||760102|
|Transmit Control Register||TCR||760104|
|Modem Status Register||MSR||760106|
|Transmit Data Register||TDR||760106|
The RBUF and LPR share an address, as do the MSR and TDR: the RBUF is read only, and the LPR is write only; the MSR is read only, and the TDR is write only. Registers marked with a '*' are word-width only, no byte operations.
Control and Status Register (CSR)
- TRDY - Transmitter Ready
- TIE - Transmitter Interrupt Enable
- SA - Silo Alarm
- SAE - Silo Alarm Enable
- Tx Line - Line ready to transmit
- RDONE - Received Done
- RIE - Receiver Interrupt Enable
- MSE - Master Scan Enable
- CLR - Clear input FIFO, CSR and UARTs
- MAINT - Maintenance loopback enabled
Receiver Buffer Register (RBUF)
Line Parameter Register (LPR)
Transmit Control Register (TCR)
Modem Status Register (MSR)
Transmit Data Register (TDR)
- DZ11-C, D, F (20mA) Field Maintenance Print Set, (MP00253)