Add Python program to test core via serial port.

tools/test_sincos_serial.py

@@ -0,0 +1,131 @@
+#!/usr/bin/python
+
+"""
+Test sine/cosine core via serial port.
+
+Sends a series of commands to the test driver via the serial port
+and verifies answers.
+
+Usage:
+  python test_sincos_serial.py /dev/ttyUSB0
+"""
+
+
+from __future__ import print_function
+import sys
+import numpy
+import serial
+import struct
+
+
+def testPhase(dev, coresel, databits, phasebits, phase):
+
+    print("\r phase=%-10d" % phase, end='')
+    sys.stdout.flush()
+
+    dev.write(struct.pack("<BBI", 0x41, 0x42 + coresel, phase))
+
+    reply = dev.read(8)
+
+    if len(reply) != 8:
+        print()
+        print("ERROR: got %d bytes from serial port while expecting 8" %
+              len(reply))
+        return
+
+    (vsin, vcos) = struct.unpack("<ii", reply)
+
+    ampl  = (1 << (databits - 1)) - 1
+    theta = 2 * numpy.pi * phase / 2.0**phasebits
+    refsin = ampl * numpy.sin(theta)
+    refcos = ampl * numpy.cos(theta)
+
+    if abs(vsin - refsin) > 1.5 or abs(vcos - refcos) > 1.5:
+        print()
+        print("phase=%d sin=%d cos=%d refsin=%.2f refcos=%.2f" %
+              (phase, vsin, vcos, refsin, refcos))
+        print("ERROR: wrong answer")
+
+
+def testCore(dev, clkmod, coresel, databits, phasebits):
+
+    if clkmod:
+        # Start clock-enable modulation.
+        dev.write("AD")
+    else:
+        # Stop clock-enable modulation.
+        dev.write("AE")
+
+    print("test least significant phase bits")
+    for p in range(64):
+        phase = p
+        testPhase(dev, coresel, databits, phasebits, phase)
+    print()
+
+    print("test most significant phase bits")
+    for p in range(64):
+        phase = p << (phasebits - 6)
+        testPhase(dev, coresel, databits, phasebits, phase)
+    print()
+
+    print("test pseudorandom phase values")
+    phase = 0
+    for i in range(5000):
+        phase = (phase + 123457) & ((1 << phasebits) - 1)
+        testPhase(dev, coresel, databits, phasebits, phase)
+    print()
+
+
+def main():
+
+    if len(sys.argv) != 2:
+        print(__doc__, file=sys.stderr)
+        print("ERROR: Invalid/missing command line arguments", file=sys.stderr)
+        sys.exit(1)
+
+    devname = sys.argv[1]
+
+    # Open serial port.
+    print("opening serial port", devname)
+    dev = serial.Serial(port=devname,
+                        baudrate=115200,
+                        bytesize=8,
+                        parity='N',
+                        stopbits=1,
+                        timeout=1)
+
+    # Flush input.
+    print("flush serial port buffer")
+    dev.flushInput()
+    dev.flushOutput()
+    dev.read(1000)
+
+    # Write series of Z to force test driver to idle state.
+    dev.write("ZZZZZZZZ")
+
+    print()
+    print('Test 18-bit data, 20-bit phase core')
+    testCore(dev, 0, 0, 18, 20)
+    print()
+
+    print('Test 24-bit data, 26-bit phase core')
+    testCore(dev, 0, 1, 24, 26)
+    print()
+
+    print('Test 18-bit data, 20-bit phase core with clock-enable modulation')
+    testCore(dev, 1, 0, 18, 20)
+    print()
+
+    print('Test 24-bit data, 26-bit phase core with clock-enable modulation')
+    testCore(dev, 1, 1, 24, 26)
+    print()
+
+    # Close serial port.
+    dev.close()
+
+    print("done")
+
+
+if __name__ == '__main__':
+    main()
+