3.6.4. Bode Analyzer

The Bode Analyzer can be used from the console.

Note

The preparation of the environment can be found in this chapter.

Bode analyzer version 2.07-494, compiled at Sat Mar 22 06:11:15 2025

Usage:  bode [channel] [amplitude] [dc bias] [averaging] [count/steps] [start freq] [stop freq] [scale type] [probe]
or
        bode -calib

        channel            Channel to generate signal on [1 / 2].
        amplitude          Signal amplitude in V [0 - 1, which means max 2Vpp].
        dc bias            DC bias/offset/component in V [0 - 1].
                        Max sum of amplitude and DC bias is (0-1] V.
        averaging          Number of samples per one measurement [>1].
        count/steps        Number of measurements [>2].
        start freq         Lower frequency limit in Hz [3 - 62.5e6].
        stop freq          Upper frequency limit in Hz [3 - 62.5e6].
        scale type         0 - linear, 1 - logarithmic.
        probe              Probe value [1-1000].
        -calib             Starts calibration mode. The calibration values will be saved in:/tmp/ba_calib.data
Output: frequency [Hz], phase [deg], amplitude [dB]

To run the bode utility, perform the following steps:

1. Load the FPGA image.

   OS version 2.00OS version 1.04 or older

   redpitaya> overlay.sh v0.94
   

2. Start the console application.

   root@rp-f09508:~# bode 1 1 0 1 10 1000 100000 0
   1000.00     0.00025    0.34855
   12000.00    0.00090    0.34481
   23000.00    0.00209    0.32803
   34000.00    0.00859    0.33696
   45000.00    0.00335    0.26568
   56000.00    -0.00580   0.38830
   67000.00    -0.01751   0.36922
   78000.00    0.00635    0.32767
   89000.00    0.00521    0.38478
   100000.00   -0.00933   0.36610
   

Source code

The Red Pitaya GitHub repository contains the source code for the bode utility.