FUNCtion Subsystem
[SOURce[1|2]:]FUNCtion:PRBS:DATA <
sequence_type
>
[SOURce[1|2]:]FUNCtion:PRBS:DATA?
Sets the pseudo-random binary sequence (PRBS) type. Setting the sequence type sets the length and feedback values
as shown below.
Parameter
Typical Return
{PN7|PN9|PN11|PN15|PN20|PN23}
Value after PN corresponds to maximum shift register length in bits.
Default is PN7.
PN7, PN9, PN11, PN15, PN20, or PN23
Set data format to PN23:
FUNC:PRBS:DATA PN23
l
SYNC Output may be active during a PRBS function, unlike the
function.
l
A PRBS waveform using polynomial PN
x
is generated by a shift register of
x
bits, and the output waveform begins
with
x
sample periods of high output. Sample period is the reciprocal of the sample rate (
),
and the channel's
Sync
pulse indicates the waveform's start. For example, if the PRBS uses PN23 with sample
rate 500 Hz, the output begins with 46 ms of high output (23 x 2 ms). The polynomials are shown below.
Sequence Type
Polynomial
Feedback
Length
PN7
x
7
+ x
6
+ 1
0x02000000
7
PN9
x
9
+ x
5
+ 1
0x04000000
9
PN11
x
11
+ x
9
+ 1
0x00400000
11
PN15
x
15
+ x
14
+ 1
0x00020000
15
PN20
x
20
+ x
17
+ 1
0x00004000
20
PN23
x
23
+ x
18
+ 1
0x00002000
23
[SOURce[1|2]:]FUNCtion:PRBS:TRANsition[:BOTH] {<
seconds
>|MI-
Nimum|MAXimum}
[SOURce[1|2]:]FUNCtion:PRBS:TRANsition[:BOTH]? [{MINimum|MAXimum}]
Sets PRBS transition edge time on both edges of a PRBS transition.
Parameter
Typical Return
8.4 ns (default) to 1 μsec, limited as described below
+1.000000000000000E-08
Set edge time to 10 ns for the leading and trailing edges (two methods):
FUNC:PRBS:TRAN 10 ns
FUNC:PRBS:TRAN .000000010
218
Agilent 33500 Series Operating and Service Guide
