DA3—Tertiary Device Attributes

In this DA exchange, the host asks for the terminal unit identification code. This ID code serves as a way to identify each terminal in a system. The unit ID code is preset at the factory.

Host Request

The host uses the following sequence to send this request:

CSI
9/11
=
3/13
c
6/3
or CSI
9/11
=
3/13
0
3/0
c
6/3

Terminal Response

The terminal responds by sending a report terminal unit ID (DECRPTUI) control string to the host. DECRPTUI is available in VT Level 4 mode only.

DCS
9/0
!
2/1
|
7/12
D . . . D
...
ST
9/12

Parameters

D...D
is the unit ID of the terminal, consisting of four hexadecimal pairs. The first pair represents the manufacturing site code. This code can be any hexadecimal value from 00 through FF.

The last three hexadecimal pairs are the terminal ID number. This number is unique for each terminal manufactured at that site.

Tertiary DA Example

Here is a typical tertiary DA exchange.

Exchange Sequence Meaning
Request (Host to Terminal) CSI = c or CSI = 0 c The host asks for the terminal unit ID.
DECRPTUI Response (Terminal to host) DCS ! | 00 01 02 05 ST The terminal was manufactured at site 00 and has a unique ID number of 125.