PDP11 PeripheralsHbk 1972 - Trailing-Edge

2 Request to Send
Data terminal Ready
o Line Enable
8.5.4 Specifications
Operating Mode:
Data Rate:
Data Format:
Order of Bit
Transmission:
Parity:
Mode of Operation:
Data Bufferi ng:
Di sto rti on:
Bus Load:
Data Signals:
This lead is used to condition the modem
for transmit if all other conditions are
met. This bit is read/write and cleared by
Initialize and Clear MUX.
This lead allows the modem to enter and
maintain data mode. This Bit is
Read/Write and cleared by Initialize and
Clear MUX.
This bit Enables the state of Ring, Carrier,
Clear to Send and Sec Rx to be sampled by
the program and for being tested for transitions.
This bit is Read/Write and is
cleared by Initialize and Clear MUX.
Full or half duplex operation selected under software
control.
From 45 to 1200 Baud Jumper selectable per 16
lines. Baud rate must be specified with order.
One start bit. Character size jumper selectable for
5-, 6-, 7-, or 8- level code. Stop code is jumper selectable
for one or two stop bits. (Must be specified
with order)
Low order bit first;
Computed on incoming data.
DMA (NPR) character assembly in core memory for
received characters. DMA (NPR) message transmission
from core memory.
One 64-character circular Buffer per DMll.
Input: can tolerate up to 42% per character.
Output: less than 2% per character.
Complete mulitplexer represents a 1 unit load to
the PDP-ll UNIBUS. The UNIBUS can handle 18
unit loads. For more than 18 uriit -loads, a bus extender,
DBII-A, must be used.
Line Adapter Output
Type Signals
DM ll-DA 20mA. Current/oop for four teletypes,
maximum distance 1500 feet.
OM II-DB EIA RS-232-C and CCITT for four lines
(data only)
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