45 lines
1.9 KiB
C
45 lines
1.9 KiB
C
/*
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* This file is part of the Micro Python project, http://micropython.org/
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*
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* The MIT License (MIT)
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*
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* Copyright (c) 2017 Dan Halbert for Adafruit Industries
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "peripherals.h"
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#include "hpl_sercom_config.h"
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// Routines that are the same across all samd variants.
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// Convert frequency to clock-speed-dependent value. Return 255 if > 255.
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uint8_t samd_peripherals_spi_baudrate_to_baud_reg_value(const uint32_t baudrate) {
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uint32_t baud_reg_value = (uint32_t) (((float) PROTOTYPE_SERCOM_SPI_M_SYNC_CLOCK_FREQUENCY /
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(2 * baudrate)) - 0.5f);
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return (uint8_t) (baud_reg_value > 255 ? 255 : baud_reg_value);
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}
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// Convert BAUD reg value back to a frequency.
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uint32_t samd_peripherals_spi_baud_reg_value_to_baudrate(const uint8_t baud_reg_value) {
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return PROTOTYPE_SERCOM_SPI_M_SYNC_CLOCK_FREQUENCY / (2 * (baud_reg_value + 1));
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}
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