24 lines
850 B
Python
24 lines
850 B
Python
# MCP4728 dac code
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#
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# Copyright (C) 2018 Kevin O'Connor <kevin@koconnor.net>
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#
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# This file may be distributed under the terms of the GNU GPLv3 license.
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from . import bus
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class mcp4728:
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def __init__(self, config):
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self.i2c = bus.MCU_I2C_from_config(config, default_addr=0x60)
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scale = config.getfloat('scale', 1., above=0.)
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# Configure registers
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for i, name in enumerate('abcd'):
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val = config.getfloat('channel_%s' % (name,), None,
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minval=0., maxval=scale)
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if val is not None:
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self.set_dac(i, int(val * 4095. / scale + .5))
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def set_dac(self, dac, value):
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self.i2c.i2c_write([0x40 | (dac << 1),
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((value >> 8) & 0x0f) | 0x80, value & 0xff])
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def load_config_prefix(config):
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return mcp4728(config)
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