94 lines
3.5 KiB
C
94 lines
3.5 KiB
C
/***************************************************************************
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* Copyright (C) 2024 by Federico Amedeo Izzo IU2NUO, *
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* Niccolò Izzo IU2KIN *
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* Frederik Saraci IU2NRO *
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* Silvano Seva IU2KWO *
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* *
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* This program is free software; you can redistribute it and/or modify *
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* it under the terms of the GNU General Public License as published by *
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* the Free Software Foundation; either version 3 of the License, or *
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* (at your option) any later version. *
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* *
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* This program is distributed in the hope that it will be useful, *
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* but WITHOUT ANY WARRANTY; without even the implied warranty of *
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
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* GNU General Public License for more details. *
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* *
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* You should have received a copy of the GNU General Public License *
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* along with this program; if not, see <http://www.gnu.org/licenses/> *
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***************************************************************************/
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#include <interfaces/delays.h>
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#include "spi_bitbang.h"
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uint8_t spiBitbang_sendRecv(const void *priv, uint8_t data)
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{
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const struct spiConfig *cfg = (const struct spiConfig *) priv;
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uint8_t incoming = 0;
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for(uint8_t cnt = 0; cnt < 8; cnt++)
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{
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// Clock inactive edge
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if((cfg->flags & SPI_FLAG_CPHA) != 0)
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gpio_setPin(cfg->clk.port, cfg->clk.pin);
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else
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gpio_clearPin(cfg->clk.port, cfg->clk.pin);
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// Setup data output
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if((data & 0x80) != 0)
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gpio_setPin(cfg->mosi.port, cfg->mosi.pin);
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else
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gpio_clearPin(cfg->mosi.port, cfg->mosi.pin);
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// Sample data input
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data <<= 1;
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incoming <<= 1;
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incoming |= gpio_readPin(cfg->miso.port, cfg->miso.pin);
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delayUs(cfg->clkPeriod);
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// Clock active edge
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if((cfg->flags & SPI_FLAG_CPHA) != 0)
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gpio_clearPin(cfg->clk.port, cfg->clk.pin);
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else
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gpio_setPin(cfg->clk.port, cfg->clk.pin);
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delayUs(cfg->clkPeriod);
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}
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return incoming;
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}
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int spiBitbang_init(const struct spiCustomDevice *dev)
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{
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const struct spiConfig *cfg = (const struct spiConfig *) dev->priv;
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// Basic driver init
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spi_init((const struct spiDevice *) dev);
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// Setup MOSI and clock lines as output, low level
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gpio_setMode(cfg->clk.port, cfg->clk.pin, OUTPUT);
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gpio_setMode(cfg->mosi.port, cfg->mosi.pin, OUTPUT);
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gpio_clearPin(cfg->mosi.port, cfg->mosi.pin);
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gpio_clearPin(cfg->clk.port, cfg->clk.pin);
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// Set MISO line as input only for full-duplex operation
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if((cfg->flags & SPI_HALF_DUPLEX) == 0)
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gpio_setMode(cfg->miso.port, cfg->miso.pin, INPUT);
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return 0;
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}
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void spiBitbang_terminate(const struct spiCustomDevice* dev)
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{
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const struct spiConfig *cfg = (const struct spiConfig *) dev->priv;
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// Set clock and MOSI back to Hi-Z state
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gpio_setMode(cfg->clk.port, cfg->clk.pin, INPUT);
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gpio_setMode(cfg->mosi.port, cfg->mosi.pin, INPUT);
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// Final driver cleanup
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spi_terminate((const struct spiDevice *) dev);
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}
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