Quantum Data 801GC, 801GF, 801GX, Owner'S And Programmer'S Manual

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VTOT Vertical TOTal lines per frame
Classification: Format parameter setting
Command Syntax: VTOT <lines>
Limits: <lines> must be an odd number when SCAN = 2
min = 2
max
801GC-ISA = 4096 @ SCAN=1; 4097 @ SCAN=2
801GF-ISA = 4096 @ SCAN=1; 8191 @ SCAN=2
801GP = 2048
801GC, GX = 4096 @ SCAN=1; 4097 @ SCAN=2
801GF = 4096 @ SCAN=1; 8191 @ SCAN=2
Query Syntax: VTOT?
Query Response: <lines>
Description: The VTOT command establishes the total number of lines per
frame. When interlacing (SCAN=2), VTOT must be odd. The
VTOT? query returns the current setting of VTOT.
The frame or picture refresh rate is equal to the quotient of
HRAT divided by VTOT.
The field or vertical rate is equal to the frame rate when SCAN
= 1 (non-interlaced operation).
The field or vertical rate is equal to twice the frame rate when
SCAN = 2 (non-interlaced operation).
Note – The current version of the firmware does not allow you
to directly enter a specific field or frame rate when setting up
a format. If your test specifications call for a specific field,
frame or vertical refresh rate, enter suitable values for HRAT,
SCAN and VTOT to give you the desired rate.
Other Required Cmds: 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:
V T O T 5 2 5 / / S e t t o t a l l i n e s / / f r a m e t o
/ / 5 2 5 i n b u f f e r
F M T U / / U p d a t e h a r d w a r e t o c u r r e n t
/ / b u f f e r c o n t e n t s