Waveform Curve - Tektronix 7D20 Operator's Manual

Waveform Curve
CURVE :
<ASCII curve> ~ <binary curve>
where:
<wfm#> : :=1 ~2 ~3 ~4~5~6
<encdg> : := ASCII ~ BINARY
<p/w> : := 820 ~ 1024
<x increment> : :_ <NR3> = time/div 1 points/div
<point #> : :_ <NR1>
<y multiplier> : :_ <NR3> = vertical scale factor
<y zero> : :_ <NR3> _ -(VZR * vertical scale factor)
<wfmid> : := W <wfm #> I ~ W <wfm #>,
where I indicates interpolated data .
1 . Curve Commands . These transmit waveform point data to the 7D20 . The
CURVE command takes two different forms :
<ASCII curve> : :_ <ASCII point>,<ASCII point> . . .
<binary curve> : :_ %<binary count><binary point> . .
<checksum> (<checksum> is defined below .)
Waveform memory extends from -5 .12 divisions to +5 .08 divisions . When
transmitting an ASCII curve, data is sent in divisions . When transmitting a binary
curve, data is sent as point numbers with 000000002 , 100000002 , 11111111 z
corresponding to -5 .12 divisions, 0 divisions (center screen), and +5 .08 divisions,
respectively . A short curve is filled out with a reiteration of the last point . Note that
an ASCII curve must have at least two points . If only one point is sent, a syntax error
code will be generated .
2 . Curve Queries . These queries transmit waveform data from the 7D20 to the
GPIB controller . The DATA command specifies whether ASCII or binary format
is to be used .
CURVE?
Responds with the current source waveform's curve :
if ASCII :
CURVE <ASCII point>,<ASCII point> . . .
if binary :
CURVE %<binary count><binary point> . . .<checksum>
where :
<ASCII point> : :_ <NR3>
<binary count> : := two bytes representing number of
data points +1 (checksum)
<binary point> : := 8-bit byte (00 ~ 01 ~ . . . ~ FE ~ FF)
<checksum> : := two's complement of the modulo 256 sum of
the preceding binary data bytes and the binary count, but not
the "%" preceding the binary byte count .
<wfmid> : := W <wfm #> I ~ W <wfm #>, (I indicates inter-
polated data .)
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