A-2. Hp-Ib Worksheet - HP 3478A Technical Manual

3478A
h. Require Service: A device can send this
message at any time to signify the device needs some
type of interaction with the controller. This message is
cleared by the device's STATUS BYTE message if the
device no longer requires service.
i. Status Byte: A byte that represents the current
status of a single device on the HP-IB. One bit indicates
whether the device sent the require sevice message and
the remaining seven bits indicate optional conditions
defined by the device. This byte is sent from the talking
device in response to a "Serial Poll" operation performed
by the controller.
j. Status Bit: A byte that represents the
operational conditions of a group of devices on the HP-
IB. Each device responds on a particular bit of the byte
thus identifying a device dependent condition. This bit is
typically sent by devices in response to a parallel poll
operation.
k. Pass Control: The bus management
responsibility is transferred from the active controller to
another controller by this message.
I. Abort: The system controller sends this
message to unconditionally assume control of the HP-IB
from the active controller. The message will terminate all
bus communication but does not implement the CLEAR
message.
A-16. 3478A Bus Capabilities
A-17. The 3478A interfaces to the HP-IB as defined
by the IEEE Standard 488-1978. The interface functional
subset which the 3478A implements is specified in Table
A-1 .
Table A-1. 3476A Device Capability
SH1 Source Handshake complete capability
AH1 Acceptor Handshake complete capability
T5 Basic talker, with serial poll, talk only
mode, and unaddress with MLA.
TEO No extended talker
L4 Basic listener, unaddress when MTA
LEO No extended listener
SR1 Service request complete capability
RL1 Remote-Local complete capability
PPO No parallel poll capability
DC1 Device Clear complete capability
DT1 Device Trigger complete capability
CO No controller capability
A-18. HP-IB Worksheet
The HP-IB worksheet (Table A-2) can be used to
determine the HP-IB capabilities of the other HP-IB
compatible instruments in a system. The sheet may be
filled in with the bus message applicability for your
controller and for each HP-IB device. The bus capability
for the 3478A has already b, en filled in. Refer to your
controller manual and the manual(s) of your other
device(s) for their Bus Message capabilities. Once the
sheet is filled out, you should then have the HP-IB
capabilities of your device(s).
A-3
TM 11-6625-3071-14