Section 2 GPIB Interface
2.6Initializing the Device
IEEE488.2 st~pulatesthree levels of system initialization: initialization of the bus, message and device.
Table 2-6 Types of System lnitialization
Level | Type of Initialization | Outline |
1 | Initialization of the bus | Initializes the functions of all the interfaces connected to the bus with the IFC |
|
| message from the controller. |
2Initialization of the message Disables the function to report to the controller that the initialization of the exchange of messages among all the devices on GPIB and relevant operations are completed by DCL, one of the GPIB bus commands, and that the initial- ization of the exchange of messages among specified devices on GPIB and relevant operations are completed by SCL, also one of the GPIB bus com- mands.
3Initialization of the device Returns the device to the original state unique to the device by *RST, regard- less of the status during past usage.
2.6.1lnitializing the Bus
IFC:Initialization of the bus by the IFC statement
Function: Switches the IFC line into an active state for about 100 ps and initializes the interface function of all the devices connected to the GPIB bus line. IFC can be transmitted only by the system controller.
2.6.2lnitializing the Message
DC'L and SDC: Initialization of the exchange of messages by the DCL and SDC bus commands
Initializes the exchange of messages for all the devices on GPIB or specified devices on GPIR.
Functions: Initialization of the message exchange is aimed at setting preparations to enable the controller to send new instructions in the event that sections related to the message exchange in devices are set in a state inappropriate for the control to be executed from the controller because, for example, other programs were executed earlier, although changing the panel setting is not required.
DCL: | Initializes the message exchange among all the devices on GPIB |
SDC: | Initializes the message exchange among specified devices. |
