/** * Copyright (c) 2011-2022 Bill Greiman * This file is part of the SdFat library for SD memory cards. * * MIT License * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included * in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. */ #ifndef SdSpiAvr_h #define SdSpiAvr_h // Use of in-line for AVR to save flash. #define nop asm volatile("nop\n\t") //------------------------------------------------------------------------------ inline void SdSpiArduinoDriver::activate() { SPI.beginTransaction(m_spiSettings); } //------------------------------------------------------------------------------ inline void SdSpiArduinoDriver::begin(SdSpiConfig spiConfig) { (void)spiConfig; SPI.begin(); } //------------------------------------------------------------------------------ inline void SdSpiArduinoDriver::deactivate() { SPI.endTransaction(); } //------------------------------------------------------------------------------ inline void SdSpiArduinoDriver::end() { SPI.end(); } //------------------------------------------------------------------------------ inline uint8_t SdSpiArduinoDriver::receive() { return SPI.transfer(0XFF); } //------------------------------------------------------------------------------ inline uint8_t SdSpiArduinoDriver::receive(uint8_t* buf, size_t count) { if (count == 0) { return 0; } #ifdef SPSR SPDR = 0XFF; while (--count) { // nops optimize loop for 16MHz CPU 8 MHz SPI nop; nop; while (!(SPSR & _BV(SPIF))) { } uint8_t in = SPDR; SPDR = 0XFF; *buf++ = in; } while (!(SPSR & _BV(SPIF))) { } *buf = SPDR; #elif defined(SPI_RXCIF_bm) SPI0.DATA = 0XFF; while (--count) { // nops optimize loop for ATmega4809 16MHz CPU 8 MHz SPI nop; nop; nop; nop; while (!(SPI0.INTFLAGS & SPI_RXCIF_bm)) { } uint8_t in = SPI0.DATA; SPI0.DATA = 0XFF; *buf++ = in; } while (!(SPI0.INTFLAGS & SPI_RXCIF_bm)) { } *buf = SPI0.DATA; #else // SPSR #error Unsupported AVR CPU - edit SdFatConfig.h to use standard SPI library. #endif // SPSR return 0; } //------------------------------------------------------------------------------ inline void SdSpiArduinoDriver::send(uint8_t data) { SPI.transfer(data); } //------------------------------------------------------------------------------ inline void SdSpiArduinoDriver::send(const uint8_t* buf, size_t count) { if (count == 0) { return; } #ifdef SPSR SPDR = *buf++; while (--count) { uint8_t b = *buf++; // nops optimize loop for 16MHz CPU 8 MHz SPI nop; nop; while (!(SPSR & (1 << SPIF))) { } SPDR = b; } while (!(SPSR & (1 << SPIF))) { } #elif defined(SPI_RXCIF_bm) SPI0.DATA = *buf++; while (--count) { uint8_t b = *buf++; // nops optimize loop for ATmega4809 16MHz CPU 8 MHz SPI nop; nop; nop; while (!(SPI0.INTFLAGS & SPI_RXCIF_bm)) { } SPI0.DATA = b; } while (!(SPI0.INTFLAGS & SPI_RXCIF_bm)) { } #else // SPSR #error Unsupported AVR CPU - edit SdFatConfig.h to use standard SPI library. #endif // SPSR } #endif // SdSpiAvr_h