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#
# Copyright (c) 2024 Analog Devices Inc.
#
# This file is part of libm2k
# (see http://www.github.com/analogdevicesinc/libm2k).
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 2.1 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
import libm2k
'''
Please check Electronics Lab 14 on our wiki page: https://wiki.analog.com/university/courses/electronics/electronics-lab-14
Configure the connections for 'Unipolar output operation' mode
'''
VOLTAGE = 2.5
def get_register_data(voltage):
if voltage < 0:
return [0, 0]
if voltage > 4.095:
return [0x0F, 0xFF]
register_value = int(voltage * 1000)
return [(register_value >> 8) & 0xFF, register_value & 0xFF]
def main():
context = libm2k.m2kOpen('ip:192.168.2.1')
if context is None:
print('Connection Error: No ADALM2000 device available/connected to your PC.')
exit(1)
context.calibrateADC()
analog_in = context.getAnalogIn()
power_supply = context.getPowerSupply()
digital = context.getDigital()
# setup analog in
analog_in.setOversamplingRatio(1)
analog_in.setSampleRate(1000000)
analog_in.enableChannel(0, True)
analog_in.enableChannel(1, False)
analog_in.setRange(libm2k.ANALOG_IN_CHANNEL_1, libm2k.PLUS_MINUS_25V)
# enable LDAC
digital.setDirection(3, libm2k.DIO_OUTPUT)
digital.enableChannel(3, True)
# enable CLR
digital.setDirection(4, libm2k.DIO_OUTPUT)
digital.enableChannel(4, True)
# setup SPI
m2k_spi_init = libm2k.m2k_spi_init()
m2k_spi_init.clock = 1
m2k_spi_init.mosi = 2
m2k_spi_init.miso = 7 # dummy value - miso is not used in this example
m2k_spi_init.bit_numbering = libm2k.MSB
m2k_spi_init.cs_polarity = libm2k.ACTIVE_LOW
m2k_spi_init.context = context
spi_init_param = libm2k.spi_init_param()
spi_init_param.max_speed_hz = 1000000
spi_init_param.mode = libm2k.SPI_MODE_3
spi_init_param.chip_select = 0
spi_init_param.extra = m2k_spi_init
spi_desc = libm2k.spi_init(spi_init_param)
if spi_desc is None:
print('SPI Error: Could not configure SPI')
exit(1)
power_supply.enableChannel(0, True)
power_supply.pushChannel(0, 5)
# CLR and LDAC high as long as bits are transmitted
digital.setValueRaw(3, libm2k.HIGH)
digital.setValueRaw(4, libm2k.HIGH)
data = bytearray(get_register_data(VOLTAGE))
# transmitting data
libm2k.spi_write_and_read(spi_desc, data)
if len(data) == 0:
print('SPI Error: Could not transmit the data')
exit(1)
# update with current shift register contents
digital.setValueRaw(3, libm2k.LOW)
samples = analog_in.getSamples(100)
average = sum(samples[0]) / len(samples[0])
print('Average value: ' + str(average))
libm2k.spi_remove(spi_desc)
libm2k.contextClose(context, True)
if __name__ == "__main__":
main()
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