Technical data

Figure 1–1 VAX 4000 Model 100A Ports, Controls, and LEDs
1
3
2
4 5 6 7 8 93 10
11 12
1 2
MLO-010220
Optional Asynchronous Communications Ports A and B—These are the
ports to which you can connect devices or options that use asynchronous
communications. Port A is on the bottom.
Optional Synchronous Communications Ports 0 and 1—These are the ports
to which you can connect the devices or options that use synchronous
communications. Port 0 is on the bottom.
Modified Modular Jack (MMJ) Ports 0, 1, and 3—These are the ports to
which you can connect the user terminal, printer or other devices that
use asynchronous DEC423 data-line-only ports to the system unit. The
console terminal is always connected to port 3.
Asynchronous Modem Control Port (Port 2)—This is the port at which you
can connect a modem, terminal, printer, or other devices that use EIA-232
ports to the system unit.
Halt Button—This button halts the system and returns it from the
operating system to console mode.
1–2 VAX 4000 Model 100A Hardware