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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 Square Wave Generator
A square wave is a periodic waveform that alternates between two discrete values. 
Here's an example square wave that is generated using a simple Python function.
Step1:  To implement our square wave in magma, we start by importing the IceStick module from loam. We instance the IceStick and turn on the Clock and J3[0] (configured as an output).
Now we'll use magma and mantle to implement a square wave generator.
Since our square wave just toggles between 0 and 1 using a fixed period, we can use any bit in a synchronous counter to implement it (choosing a certain counter bit will change the period).
Step2:  Compile and build the circuit.
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Python Code:
import matplotlib.pyplot as plt
import numpy as np
%matplotlib inline
x = np.arange(0, 100)
def square(x):
    return (x % 50) < 25
plt.plot(x, square(x))
import magma as m
m.set_mantle_target("ice40")
Explanation: Square Wave Generator
A square wave is a periodic waveform that alternates between two discrete values. 
Here's an example square wave that is generated using a simple Python function.
End of explanation
import mantle
from loam.boards.icestick import IceStick
icestick = IceStick()
icestick.Clock.on()
icestick.J3[0].output().on()
main = icestick.main()
counter = mantle.Counter(32)
square = counter.O[9]
m.wire( square, main.J3 )
Explanation: To implement our square wave in magma, we start by importing the IceStick module from loam. We instance the IceStick and turn on the Clock and J3[0] (configured as an output).
Now we'll use magma and mantle to implement a square wave generator.
Since our square wave just toggles between 0 and 1 using a fixed period, we can use any bit in a synchronous counter to implement it (choosing a certain counter bit will change the period).
End of explanation
m.compile('build/square', main)
%%bash
cd build
cat square.pcf
yosys -q -p 'synth_ice40 -top main -blif square.blif' square.v
arachne-pnr -q -d 1k -o square.txt -p square.pcf square.blif 
icepack square.txt square.bin
iceprog square.bin
Explanation: Compile and build the circuit.
End of explanation
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