Option 1: Test on the PC.
If your DSP code is written in C, then you can set up a test harness in GCC or Visual Studio. You know the sample rate for your DSP code, so use Excel to generate a test input CSV file, and have your test harness dump a CSV file output which you can check.
Option 2: Test on the DSP with a PC interface.
If your DSP code has to run on the DSP, you can still use the PC to test it. Set up a test harness on the DSP which receives a value from the PC, runs one step of the DSP filter, and then reports the filter output for that step back to the PC (using USB, RS-232 or TCP/IP depending on how you're connecting to the DSP). You'll also need a PC-side test harness to send and receive those values. Again, you can set up a test input CSV file on the PC, pass successive samples to the filter code, and dump a CSV file output which you can check.
If you're filtering at 0.05Hz, chances are your sample rate is going to be fairly slow too. Using a test harness will let you run these tests faster than real-time, which will make your testing process more efficient.