566 Appendix A Command Reference
VSPP Vertical Sync Pulse Polarity
Class Format parameter setting - Synchronization
Description Establishes the logic sense of the digital vertical sync outputs. Setting polarity to 1 causes
the leading edge of vertical sync to be a low-to-high transition. Setting polarity to 0 causes
the leading edge of vertical sync to be a high-to-low transition. The VSPP? query returns
the current polarity of VSPP.
Command syntax VSPP polarity
polarity
0 = high-to-low transition
1 = low-to-high transition
Query syntax VSPP?
Query response 0 or 1
Other required
commands In order to use digital vertical sync, it must be gated on with the VSPG command and
digital separate H and V sync must be selected with the SSST command. The FMTU
command instructs the generator to use the new setting. The ALLU command updates
hardware to the new setting and redraws the test image.
Example
VSPP 1 // Set active hi V sync in buffer
VSPG 1 // Enable V sync output in buffer
SSST 1 // Select H&V sync type in buffer
FMTU // Update hardware to current buffer contents