circuitpython/tools/swo_viewer.py

68 lines
1.6 KiB
Python

"""This prints out all parsed ITM packets.
Connect a USB to Serial converter to the SWO pin and then provide the serial
device to this script. It should be 1MBaud SWO signal. CTRL-C when you've
captured enough data and then it'll process and output.
pip install pysigrok-libsigrokdecode
python tools/swo_viewer.py /dev/ttyACM0
"""
import serial
import sys
import sigrokdecode
import time
import json
decoder = sigrokdecode.get_decoder("arm_itm")()
decoder.reset()
decoder.options = {"objdump": "", "elffile": ""}
decoder.start()
dwt_timestamp = 0
last_dwt_timestamp = 0
streak = 0
stack = []
def decoder_cb(ss, es, data):
global streak
global last_dwt_timestamp
print(dwt_timestamp, ss, es, data)
decoder.add_callback(sigrokdecode.OUTPUT_ANN, None, decoder_cb)
s = serial.Serial(sys.argv[-2], 1000000)
buffers = []
while True:
try:
start_ts = time.monotonic_ns()
b = s.read(s.in_waiting)
if b:
end_ts = time.monotonic_ns()
buffers.append((start_ts, end_ts, b))
# print(len(b))
# if len(buffers) > 10:
# break
except KeyboardInterrupt:
break
time_per_bit = 1_000_000_000 / 1000000
min_gap = 100000000
total_bytes = 0
for start_ts, end_ts, buf in buffers:
# print(total_bytes, start_ts, end_ts, buf)
ts_per_byte = (end_ts - start_ts) / len(buf)
for i, b in enumerate(buf):
# print(total_bytes, hex(b))
total_bytes += 1
decoder.decode(
start_ts + ts_per_byte * i, start_ts + ts_per_byte * (i + 1), ("DATA", None, (b,))
)
dwt_timestamp = decoder.dwt_timestamp