Measurement Computing Digital HS - Manual (Page 29)

Untalk (UNT) places the Digital488HS/32 in the Talker Idle State.
2.4.10 Serial Poll Response
Whenever the Digital488HS/32 generates a service request (SRQ), a serial poll by the
controller returns a serial poll status byte of at least 64 (decimal) showing the SRQ
was generated by the Digital488HS/32. For more information, see section 3.3.
2.4.11 Parallel Poll Response
The Digital488HS/32 outputs its individual status message (ist) on the IEEE 488 bus
data line determined by the setting of the three least significant bus address switches
(IEEE Address 1, 2, 4). For example, with the factory default address of 18, the data
line chosen is DIO3 (data bit line 2). See section 3.4 for more information
2.5 Front Panel Indicators
Six indicator lights on the front panel of the Digital488HS/32 display the status of the
interface. The function of each indicator is described below.
POWER On when power is applied to the Digital488HS/32 and the power switch
on the back panel is depressed. Off if power is not present.
TALK On when the Digital488HS/32 is in the IEEE 488 Talker state,
off when the Digital488HS/32 is in the Idle or Listener state.
LISTEN On when the Digital488HS/32 is in the IEEE 488 Listener state,
off when the Digital488HS/32 is in the Idle or Talker state.
SRQ On when the Digital488HS/32 has generated an IEEE 488 service request
(SRQ), off when no SRQ from the Digital488HS/32 is pending.