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stmhal/boards/pllvalues.py: Make script work with both Python 2 and 3.

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Damien George 2017-08-24 22:43:36 +10:00
parent 3e1412a1fb
commit 7e6881cf7d
1 changed files with 6 additions and 1 deletions
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stmhal/boards/pllvalues.py
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@ -4,6 +4,8 @@ the CPU frequency to a given value. The algorithm here appears as C code
for the machine.freq() function. for the machine.freq() function.
""" """
from __future__ import print_function
def close_int(x): def close_int(x):
return abs(x - round(x)) < 0.01 return abs(x - round(x)) < 0.01
@ -38,7 +40,10 @@ def compute_pll(hse, sys):
# improved version that doesn't require N/M to be an integer # improved version that doesn't require N/M to be an integer
def compute_pll2(hse, sys): def compute_pll2(hse, sys):
for P in (2, 4, 6, 8): # allowed values of P # Loop over the allowed values of P, looking for a valid PLL configuration
# that gives the desired "sys" frequency. We use floats for P to force
# floating point arithmetic on Python 2.
for P in (2.0, 4.0, 6.0, 8.0):
Q = sys * P / 48 Q = sys * P / 48
# Q must be an integer in a set range # Q must be an integer in a set range
if not (close_int(Q) and 2 <= Q <= 15): if not (close_int(Q) and 2 <= Q <= 15):