upsilon/client/util.py

108 lines
2.9 KiB
Python

"""
Copyright 2023 (C) Peter McGoron
This file is a part of Upsilon, a free and open source software project.
For license terms, refer to the files in `doc/copying` in the Upsilon
source distribution.
"""
from math import log10, floor
from decimal import *
def sign_extend(value, bits):
"""
Interpret ``value`` as a twos-complement integer of ``bits`` length.
:param value: Twos-complement integer with finite bit width.
:param bits: Bit length of ``value``.
:return: ``value`` converted to a Python integer.
"""
# Check the sign bit of the integer.
is_signed = (value >> (bits - 1)) & 1 == 1
# If not signed, just return the integer.
if not is_signed:
return value
# Otherwise,
# 1. Do an explicit twos-complement negation
# 2. Mask all the non-sign bits
# This returns the positive value as a standard Python integer.
# Then the function negates the positive integer to get the negative
# one back.
return -((~value + 1) & ((1 << (bits - 1)) - 1))
def connect_execute(f, *arg):
from pssh.clients import SSHClient # require parallel-ssh
print('connecting')
client = SSHClient('192.168.1.50', user='root', pkey='~/.ssh/upsilon_key')
# Upload the script.
print('connected')
client.scp_send(f'../linux/{f}', '/root/')
# Run the script.
args = f'micropython {f} {" ".join([str(s) for s in arg])}'
print(f"running {args}")
return client.run_command(args)
# Functions for converting to and from fixed point in Python.
def string_to_fixed_point(s, fracnum):
l = s.split('.')
if len(l) == 1:
return int(s) << fracnum
elif len(l) != 2:
return None
dec = 10
frac = 0
frac_decimal = Decimal(f'0.{l[1]}')
# get the smallest power of ten higher then frac_decimal
frac = 0
# Example:
# 0.4567 = 0.abcdefgh...
# where abcdefgh are binary digits.
# multiply both sides by two:
# 0.9134 = a.bcdefgh ...
# therefore a = 0. Then remove the most significant digit.
# Then multiply by 2 again. Then
# 1.8268 = b.cdefgh ...
# therefore b = 1. Then take 8268, and so on.
for i in range(0,fracnum):
frac_decimal = frac_decimal * 2
div = floor(frac_decimal)
frac = div | (frac << 1)
frac_decimal = frac_decimal - div
whole = int(l[0])
if whole < 0:
return -((-whole) << fracnum | frac)
else:
return whole << fracnum | frac
def fixed_point_to_string(fxp, fracnum):
whole = str(fxp >> fracnum)
mask = (1 << fracnum) - 1
fracbit = fxp & mask
n = 1
frac = ""
if fracbit == 0:
return whole
# The same method can be applied backwards.
# 0.1110101 = 0.abcdefgh ...
# where abcdefgh... are decimal digits. Then multiply by 10 to
# get
# 1001.0010010 = a.bcdefgh ...
# therefore a = 0b1001 = 9. Then use a bitmask to get
# 0.0010010 = 0.bcdefgh ...
# etc.
for i in range(0, fracnum):
fracbit = fracbit * 10
frac = frac + str(fracbit >> fracnum)
fracbit = fracbit & mask
return whole + "." + frac