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Appendix B: GPIB System Concepts
2714 & 2715 Programmer Manual
B–19
The actual parallel poll takes place after each instrument has been completely
configured. The concept is to have the controller receive one data byte that
contains status information on all of the addressed instruments. To receive this
status byte, the controller asserts EOI and the ATN line. The assertion of EOI
may coincide with ATN or occur later, so long as both are asserted. This may
occur any time after the last PPE message. The controller then reads data bus
lines while ATN and EOI are asserted to interpret the status of all selected
instruments.
To conclude the parallel poll, the controller releases EOI and then ATN. The
instrument(s) does not need to be configured for each subsequent parallel poll.
The PPU (Parallel Poll Unconfigure) command will clear all device configura-
tions and prevent them from responding to future polls. The PPD (Parallel Poll
Disable) command accomplishes essentially the same results, except that the PP
function remains in the “configured” state. PPU is a universal command (all
instruments) while PPD is used with PPC and becomes an addressed command
(only those devices selected with PPC will accept PPD).
Summary of Contents for 2714
Page 4: ......
Page 11: ...Introduction ...
Page 12: ......
Page 38: ...Introduction to Programming 1 26 2714 2715 Programmer Manual ...
Page 39: ...Message Structure ...
Page 40: ......
Page 54: ...Instrument Specific Message Structure 2 14 2714 2715 Programmer Manual ...
Page 55: ...Functional Groups ...
Page 56: ......
Page 85: ...Command Query ...
Page 86: ......
Page 179: ...Status Reporting ...
Page 180: ......
Page 197: ...Programming ...
Page 198: ......
Page 266: ...Programming 6 68 2714 2715 Programmer Manual ...
Page 267: ...Appendices ...
Page 268: ......
Page 276: ...Appendix A RS 232 Concepts A 8 2714 2715 Programmer Manual ...
Page 296: ...Appendix B GPIB System Concepts B 20 2714 2715 Programmer Manual ...
Page 297: ...Index ...
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