Tests for Notch and Lowpass filter in python

testing/testFilters.py

+#!/usr/bin/env python3
+
+import unittest
+import time
+from math import exp, cos, sin, pi, nan
+from glob import glob
+from os import system, popen, environ
+from random import random, randint
+
+BASE_BOARD="/dev/sis8300"
+REG_NOTCH1="0x43f"
+REG_NOTCH2="0x440"
+REG_NOTCH3="0x441" # enable/disable
+
+REG_LP1="0x442"
+REG_LP2="0x443"
+REG_LP3="0x444" # enable/disable
+
+PV_NOTCH_FREQ=":NOTCHFIL-FREQ"
+PV_NOTCH_BWIDTH=":NOTCHFIL-BWIDTH"
+PV_NOTCH_EN=":NOTCHFIL-EN"
+
+PV_LP_EN=":CAVLPFIL-EN"
+PV_LP_CUTOFF=":CAVLPFIL-CUTOFF"
+
+PV_F_SAMP=":F-SAMPLING"
+PV_N=":IQSMPL-NEARIQN"
+
+
+"""Get then number of a board string
+"""
+def getNumBoard(b):
+    return int(b.split("-")[1])
+
+"""Return the path to board on system"""
+def getBoard(n = 0):
+    boards = (glob(BASE_BOARD + "*"))
+    boards.sort(key=getNumBoard)
+    return (boards[n])
+
+def readReg(board, reg):
+    p = popen("sis8300drv_reg %s %s" % (board, reg))
+    ret = p.read().split("\n")[0]
+    p.close()
+
+    return ret
+
+
+def flot2Qmn(val, m, n, signed):
+    pow_2_frac_bits = float(0x1 << n)
+    pow_2_frac_bits_int_bits = float(0x1 << (m + n))
+
+    val_int64 = int(val * pow_2_frac_bits)
+    # Check if signed
+    if (signed): 
+        if (val_int64 < 0):
+            val_int64 += int(pow_2_frac_bits_int_bits)
+        # check upper limit of signed int
+        elif (val_int64 > (pow_2_frac_bits_int_bits / 2.0 - 1.0)): 
+            return nan
+
+    if (val_int64 >> m + n):
+        return nan
+
+    return val_int64
+
+class TestLowPass(unittest.TestCase):
+    def __init__(self, *args, **kw):
+        super().__init__(*args, **kw)
+        self.board = getBoard()
+        self.PV = environ.get("LLRF_IOC_NAME") + "1"
+
+    def calc_consts(self, cutoff, fsamp, n):
+        omg0 = 2*pi*cutoff 
+        h = 1/(fsamp/n)
+
+        constA = round(-exp(-omg0*h), 12)
+        constB = round(1 - exp(-omg0*h), 12)
+
+        return [constA, constB]
+
+    def test_enable(self):
+        system("caput %s %f > /dev/null" % (self.PV + PV_LP_EN, 1))
+        res = readReg(self.board, REG_LP3)
+
+        self.assertEqual(res, "0x1")
+
+        system("caput %s %f > /dev/null" % (self.PV + PV_LP_EN, 0))
+        res = readReg(self.board, REG_LP3)
+
+        self.assertEqual(res, "0x0")
+
+    def test_randValues(self):
+        cutoff = random()*10
+        fsamp = round(random()*100 + 100, 2)
+        n = float(randint(1,10))
+
+        system("caput %s %f > /dev/null" % (self.PV + PV_LP_CUTOFF, cutoff))
+        system("caput %s %f > /dev/null" % (self.PV + PV_F_SAMP, fsamp))
+        system("caput %s %f > /dev/null" % (self.PV + PV_N, n))
+
+        res = self.calc_consts(cutoff, fsamp, n)
+
+        a = flot2Qmn(res[0], 1, 15, 1)
+        self.assertNotEqual(a, nan)
+        b = flot2Qmn(res[1], 1, 15, 1)
+        self.assertNotEqual(b, nan)
+        
+        a = hex(a)
+        b = hex(b)
+    
+        reg1 = readReg(self.board, REG_LP1)
+        self.assertEqual(str(a), reg1)
+
+        reg2 = readReg(self.board, REG_LP2)
+        self.assertEqual(str(b), reg2)
+
+
+class TestNotch(unittest.TestCase):
+    def __init__(self, *args, **kw):
+        super().__init__(*args, **kw)
+        self.board = getBoard()
+        # TODO: after fix LLRF_IOC_NAME change this
+        self.PV = environ.get("LLRF_IOC_NAME") + "1"
+
+    # calculate and return constants from Notch
+    def calc_consts(self, bd, freq, fsamp, n):
+        h = 1/(fsamp/n);
+        omg0 = 2*pi*freq;
+        xi0 = bd/(2*freq);
+
+        areal = round(exp(-(xi0*omg0*h))*cos(omg0*h), 12)
+        aimag = round(exp(-(xi0*omg0*h))*sin(omg0*h), 12)
+        breal = round((1-exp(-(xi0*omg0*h)))*cos(omg0*h), 12)
+        bimag = round((1-exp(-(xi0*omg0*h)))*sin(omg0*h), 12)
+
+        return([areal, aimag, breal, bimag])
+       
+    # test random values 
+    def test_randValues(self):
+        freq = random()*10
+        bwidth = random()*10
+        fsamp = round(random()*100 + 100, 2)
+        n = float(randint(1,10))
+
+        system("caput %s %f > /dev/null" % (self.PV + PV_NOTCH_FREQ, freq))
+        system("caput %s %f > /dev/null" % (self.PV + PV_NOTCH_BWIDTH, bwidth))
+        system("caput %s %f > /dev/null" % (self.PV + PV_F_SAMP, fsamp))
+        system("caput %s %f > /dev/null" % (self.PV + PV_N, n))
+
+        res = self.calc_consts(bwidth, freq, fsamp, n)
+
+        areal = flot2Qmn(res[0], 1, 15, 1)
+        self.assertNotEqual(areal, nan)
+        aimag = flot2Qmn(res[1], 1, 15, 1)
+        self.assertNotEqual(aimag, nan)
+        breal = flot2Qmn(res[2], 1, 15, 1)
+        self.assertNotEqual(breal, nan)
+        bimag = flot2Qmn(res[3], 1, 15, 1)
+        self.assertNotEqual(bimag, nan)
+
+        reg1exp = hex((areal << 16) | aimag)
+        reg2exp = hex((breal << 16) | bimag)
+    
+        reg1 = readReg(self.board, REG_NOTCH1)
+        self.assertEqual(str(reg1exp), reg1)
+
+        reg2 = readReg(self.board, REG_NOTCH2)
+        self.assertEqual(str(reg2exp), reg2)
+
+
+    # check if enable works
+    def test_enable(self):
+        system("caput %s %f > /dev/null" % (self.PV + PV_NOTCH_EN, 1))
+        res = readReg(self.board, REG_NOTCH3)
+
+        self.assertEqual(res, "0x1")
+
+        system("caput %s %f > /dev/null" % (self.PV + PV_NOTCH_EN, 0))
+        res = readReg(self.board, REG_NOTCH3)
+
+        self.assertEqual(res, "0x0")
+
+       
+
+if __name__ == "__main__":
+    unittest.main()