ICS ELECTRONICS 4863, Руководство пользователя

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If the 4863's input string is being read transparently, it is necessary to
Untalk the 4863 between readings. This can be done by addressing
another instrument, by serial polling the 4863, by sending the 4863 a
command or by adding a Untalk to your program. Most GPIB command
libraries have a CMD or SEND instruction that can output an Untalk
command (UNT or the ASCII _ character).
e.g. CALL ieSend("UNT") 'ICS's 488-PC2 syntax
CALL SendCmd(Bd%, "\x5F",1) 'NI 488.2 syntax
If you do not receive data, query the Event Status Register (ESR) to
determine the state of the 4863's EDR flip-flop. (It must be on to read data
if handshaking is enabled.). If ESR bit 6 is set, the data is ready to be read.
If the bit is not set, the EDR input line was not pulsed.
e.g. *ESR? 'Queries register status
ENTER dev, A 'Reads 4863 response
AND( A, #h40) 'Tests bit 6
3.8.3 Other Functions
The following sections describe other useful 4863 functions.
3.8.3.1 Triggering the External Device
Triggering provides a way to control when an external device performs
some action. Triggers can be single shot or continuous. Use the SCPI
INITATE subsystem to enable the trigger output.
e.g. INITiate:CONTinuous ON 'Enables continuous triggers
*TRG 'Generates the trigger pulse
The 4863 responds to a *TRG command or a 488.1 GET command by
pulsing its trigger output line. Any other action depends upon the external
device. Provide a delay for the triggered action to occur before reading the
input data.