Black Box 488 Controller, Руководство пользователя

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488 CONTROLLER
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SYNTAX MASK {ON | OFF}
RESPONSE None
MODE Any
BUS STATES None
EXAMPLE:
PRINT#1,"MASK ON"
MEMORY Command
The MEMORY command returns the amount of memory which, at the time the command is executed,
is available in the USER heap.
SYNTAX MEMORY or ME
RESPONSE numeric value of the remaining memory in the USER heap
MODE Any
BUS STATES None
EXAMPLE:
PRINT#1,"MEMORY" Request amount of available memory
INPUT#1,M : PRINT M
ON <event> DOMACRO Command
The ON <event> DOMACRO command allows the 488 Controller to automatically execute a macro when
one or more of the specified events occur. The events are polled between commands; when one of the
events is detected as true, its assigned macro is executed. Once executed, the event is disabled from further
execution and must be re-enabled with another ON <event> DOMACRO command.
There are two types of events: level-sensitive and edge-sensitive. Level-sensitive events, such as SRQ, will cause
macro execution every time they are enabled while the event condition persists. Usually, some action must
be taken (for example, SPOLL) to clear the condition prior to re-issuing the ON <event> DOMACRO
command. Edge-sensitive events, such as TRIGGER, are cleared when the macro executes.
Regardless of the event sensitivity, the ON <event> DOMACRO command must be resent after the macro
executes to reactivate the event condition. The optional events include:
SRQ This event is level-sensitive. If the condition exists at the time the ON SRQ DOMACRO
command is issued, the 488 Controller will execute the assigned macro immediately.
PERIPHERAL This event occurs when the 488 Controller is forced from the Controller Active State
(*SC-CA) to the Peripheral State (*SC-*CA) by receipt of IFC from the System
Controller. This can be useful in detecting receipt of IFC when in the *SC-CA state.
This event is edge-sensitive.