Source code for pynq.lib.pmod.pmod_dac

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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)