Technical data

4.5.3 Connecting Peripherals to an Optional Asynchronous Port
There are three asynchronous communications options for the VAX 4000 Model
100A:
• DHW42-AA—Provides one eight-line data-line-only asynchronous port
• DHW42-BA—Provides two eight-line data-line-only asynchronous ports
• DHW42-CA—Provides two four-line asynchronous ports with modem
control
Connecting Peripherals to a DHW42-AA or DHW42-BA Option
If the system has the DHW42-AA or DHW42-BA asynchronous communications
option installed, the system has one or two eight-line data-only asynchronous
ports. You can connect up to eight peripherals to each of these ports using the
H3104 harmonica. Section 4.1 gives more information on the DHW42-AA and
DHW42-BA asynchronous communications options.
To connect a peripheral to an asynchronous port, follow these steps:
1. Set the on/off switch on the peripheral to the off (O) position.
2. Connect the straight connector of the BC16C-10 cable to one of the
asynchronous ports on the back of the system unit (see Figure 4–6).
3. Close the bail lock loops on each side of the connector.
4. Connect the angled connector of the BC16C-10 cable to the H3104
harmonica.
5. Close the bail lock loops on each side of the connector.
6. Connect one end of a DEC423 cable to one of the eight MMJ ports on the
harmonica.
7. Connect the other end of the DEC423 cable to a DEC423 port on the
peripheral.
8. Set the on/off switch on the peripheral to the on (|) position.
4–18 Hardware Options