Newport MM4006, Руководство пользователя

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MM4006 A p p e n d i x B I E E E -488 Link Characteristics
IEEE-488 Function Subsets
This controller support the many GPIB function subsets, as listed bellow.
Some of the listings described subsets that the controller does not support.
CO (Controller). The MM4006 can not control other devices.
T5 (Talker). The MM4006 becomes a Talker when the CIC (Controller In
Charge) sends its TAD (Talker Address) with the ATN (Attention) line
asserted. It ceases to be a talker when the CIC (Controller In Charge) sends
another device's TAD ('l'alker Address) with ATN (Attention) asserted.
L4 (Listener). The MM4006 becomes Listener when the CIC (Controller In
Charge) sends its LAD (Listener Address) with the ATN line asserted. The
MM4006 does not have Listen Only capability.
SH1 (Source Handshake). The MM4006 can transmit multiline messages
accros the GPIB.
AH1 (Acceptor Handshake). The MM4006 can receive multiline messages
accros the GPIB.
SR1 (Service Request). The MM4006 asserts SRQ (Serial Request) line to
notify the CIC (controller In Charge) when it requires service.
RLO (Remote/Local). The MM4006 does not support the GTL (Go To Local)
and LLO (Local Lock Out) functions.
PPO (Parralel Poll). The MM4006 has no Parallel Poll capability. It does not
respond to the following interface messages: PPC, PPD, PPE and PPU. The
MM4006 does not send out a message when the ATN (Attention) and E01
(End or Identify) line are asserted.
DC1 (Device Clear). The MM4006 responds to the DCL (Device Clear) and,
when made Listener, the SDC (Selected Device Clear) interface message.
DTO (Device Trigger). The MM4006 does not support GET (Group Execute
Trigger) interface message.
E2 (Electrical). The MM4006 uses tristate buffers to provide optimal high-
speed data transfer.
SRQ Using
The NI488.2 User Manual for Windows from National Instruments, in the
GPIB Programming Techniques chapter describes the use of Serial Polling
as follow (page 7-5):
Serial Polling
You can use serial polling to obtain specific information from GPIB devices
when they request service. When the GPIB SRQ line is asserted, it signals
the Controller that a service request is pending. The controller must then
determine which device asserted the SRQ line and respond accordingly.
The most common method for SRQ detection and servicing is serial poll.
This section describes how you can set up your application to detect and
respond to service requests from GPIB devices.
Service Requests from IEEE-488 Devices
IEEE-488 devices request service from the GPIB Controller by asserting the
GPIB SRQ line. When the Controller acknowledge the SRQ, it serial polls
each open device on the bus to determine which device requested service.
Any device requesting service returns a status byte with bit 6 set and then
unasserts the SRQ line. Devices not requesting service return a status byte
with bit 6 cleared. Manufacturers of IEEE-488 devices use lower order bits
to communicate the reason for the service request or to summarize the
state of the device.
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N e w p o r t 8 . 7 E D H 0 1 8 1 E n 1020 — 03/03