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from . import Pmod
__author__ = "Graham Schelle, Giuseppe Natale, Yun Rock Qu"
__copyright__ = "Copyright 2016, Xilinx"
__email__ = "pynq_support@xilinx.com"
PMOD_DAC_PROGRAM = "pmod_dac.bin"
FIXEDGEN = 0x3
[docs]class Pmod_DAC(object):
"""This class controls a Digital to Analog Converter Pmod.
The Pmod DA4 (PB 200-245) is an 8 channel 12-bit digital-to-analog
converter run via AD5628.
Attributes
----------
microblaze : Pmod
Microblaze processor instance used by this module.
"""
def __init__(self, mb_info, value=None):
"""Return a new instance of a DAC object.
Note
----
The floating point number to be written should be in the range
of [0.00, 2.50].
Parameters
----------
mb_info : dict
A dictionary storing Microblaze information, such as the
IP name and the reset name.
"""
self.microblaze = Pmod(mb_info, PMOD_DAC_PROGRAM)
if value:
self.write(value)
[docs] def write(self, value):
"""Write a floating point number onto the DAC Pmod.
Note
----
Input value must be in the range [0.00, 2.50]
Parameters
----------
value : float
The value to be written to the DAC.
Returns
-------
None
"""
if not 0.00 <= value <= 2.5:
raise ValueError("Requested value not in range [0.00, 2.50].")
# Calculate the voltage value and write to DAC
int_val = int(value / 0.0006105)
cmd = (int_val << 20) | FIXEDGEN
self.microblaze.write_blocking_command(cmd)