Troubleshooting Terminal, Printer, and Serial Device Connections - Edition 5 (32022-90058)

General Information
Datacommunications and Terminal Subsystem (DTS)
Chapter 1
16
Datacommunications and Terminal Subsystem (DTS)
With the exception of the system console which has its own access port, all asynchronous
serial devices can be connected to HP 3000 Series 900 computers through the
Datacommunications and Terminal Subsystem (DTS). DTS is made up of all of the
Datacommunications and Terminal Controllers connected to the system, a LAN
Interface Card, the LAN cable and the host software that controls all the related DTS
hardware.
Datacommunications and Terminal Controller
The Datacommunications and Terminal Controller (DTC) provides the connection
between asynchronous devices and the HP 3000 Series 900 family of computers. The
DTC can house an X.25 Network Access Card to provide connections for nailed
PAD-connected terminals and printers. Also, a DTC containing a Telnet Access Card can
provide Telnet connections to an HP 9000 or other ARPA machine via Telnet/iX.
The DTC is housed in its own box, outside the system cabinet. This alleviates system
limitations which are based on cabinet space considerations, and allows flexibility in the
layout of terminal cables. Figure 1-1represents the location of the DTCs in relation to the
system, the LAN, and the terminals and printers connected to the system through the
DTCs.
Figure 1-1 Datacommunications and Terminal Controller
Each HP 2345B DTC (DTC 48) can provide connections for up to 48 local devices, 36
remote devices using modems, or a combination of both. For the DTC 48, up to three of
the DTC’s slots can contain a DTC/X.25 Network Access card. This card provides