I am looking for some advice on python scripting into pure data. The plan is to receive an incoming voltage via the High-Precision AD/DA Board into the Raspberry Pi, then have that changing voltage modulate parameters within Pure Data via Python. I have bastardised code from both an example from the AD board to read voltage and a tutorial to send messages from Python to Pure Data which both work. My question is, how would I go about writing the python code to send the voltage readings from one channel of the AD board to manipulate in real time a fader in pure data? Here's the Python code I am currently working with:
import os
import sys
import time
import numpy as np
import itertools
from pipyadc.ADS1256_definitions import *
from pipyadc import ADS1256
import pipyadc.ADS1256_default_config as myconfig_2
def send2pd(message=''):
os.system("echo '" + message + "' | pdsend 3000")
def AudioOn():
message = '0 1;'
send2Pd(message)
def Start_Stop():
message = '2 1;'
send2Pd(message)
def Set_Fader():
message = '1 ' + str() + ';'
send2Pd(message)
send2pd('0 1;')
send2pd('2 1;')
POTI = POS_AIN0|NEG_AINCOM
LDR = POS_AIN1|NEG_AINCOM
EXT2, EXT3, EXT4 = POS_AIN2|NEG_AINCOM, POS_AIN3|NEG_AINCOM, POS_AIN4|NEG_AINCOM
EXT5, EXT6, EXT7 = POS_AIN5|NEG_AINCOM, POS_AIN6|NEG_AINCOM, POS_AIN7|NEG_AINCOM
POTI_INVERTED = POS_AINCOM|NEG_AIN0
SHORT_CIRCUIT = POS_AIN0|NEG_AIN0
CH_SEQUENCE = (POTI, LDR, EXT2, EXT3, EXT4, EXT7, POTI_INVERTED, SHORT_CIRCUIT)
CH_OFFSET = np.array((-10, 0, -85, 0, 750, 0, 0, 0), dtype=np.int)
GAIN_CAL = np.array((1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0), dtype=np.float)
FILTER_SIZE = 32
def do_measurement():
ads2 = ADS1256(myconfig_2)
ads2.drate = DRATE_30000
ads2.cal_self()
CH_GAIN = ads2.v_per_digit * GAIN_CAL
rows, columns = FILTER_SIZE, len(CH_SEQUENCE)
filter_buffer = np.zeros((rows, columns), dtype=np.int)
timestamp = time.time()
for data_row in itertools.cycle(filter_buffer):
ads2.read_sequence(CH_SEQUENCE, data_row)
elapsed = time.time() - timestamp
if elapsed > 1:
timestamp += 1
ch_unscaled = np.average(filter_buffer, axis=0) - CH_OFFSET
ch_volts = ch_unscaled * CH_GAIN
nice_output([int(i) for i in ch_unscaled], ch_volts)
def nice_output(digits, volts):
sys.stdout.write(
"\0337"
+
"""
These are the sample values converted to voltage in V for the channels:
Poti_CH0, LDR_CH1, AIN2, AIN3, AIN4, AIN7, Poti NEG, Short 0V
"""
+ ", ".join(["{: 8.0f}".format(i) for i in volts])
+ "\n\033[J\0338"
)
send2pd
('1 ' + str() + ';') #fader send
try:
print("\033[2J\033[H")
print(__doc__)
print("\nPress CTRL-C to exit.")
do_measurement()
except (KeyboardInterrupt):
print("\n"*8 + "User exit.\n")
send2pd('2 0;')
send2pd('0 0;')
Any advice on how to do this or a better/simpler way of achieving this will be much appreciated Thanks.
