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import audio
import radio
from microbit import button_a, button_b, display, running_time, sleep
import os
def sample_generator(filename):
buf = audio.AudioFrame()
with open(filename, "rb") as file:
ln = -1
while ln:
ln = file.readinto(buf)
yield buf
# 1 second of 128Hz sawtooth wave.
def sawtooth_generator():
sawtooth = audio.AudioFrame()
for i in range(32):
sawtooth[i] = i*8+4
for i in range(256):
yield sawtooth
def send():
display.clear()
radio.on()
radio.config(channel=90, power=4)
if "sample.raw" in os.listdir():
gen = sample_generator("sample.raw")
else:
gen = sawtooth_generator()
start = running_time()
sent = 0
for f in gen:
# One frame every 4ms = 8kHz
while sent > ((running_time() - start) >> 2) + 3:
sleep(1)
radio.send_bytes(f)
sent += 1
print(sent)
def play():
display.clear()
radio.on()
radio.config(channel=90, queue=12)
count = -1
def gen():
recvd = audio.AudioFrame()
empty = audio.AudioFrame()
while True:
if radio.receive_bytes_into(recvd) == 32:
yield recvd
else:
yield empty
if button_a.is_pressed() and button_b.is_pressed():
return
audio.play(gen())
while True:
message = "Press button a to send 'sample.raw' or sawtooth wave. Press button b to play received waveform. Press both buttons to stop."
display.scroll(message, delay=100, wait=False)
message_end = running_time() + len(message)*600
if button_a.is_pressed() and button_b.is_pressed():
break
while True:
sleep(50)
if button_a.is_pressed():
send()
break
if button_b.is_pressed():
play()
break
if running_time() > message_end:
break
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