1
0
mirror of https://github.com/MarlinFirmware/Marlin.git synced 2024-12-15 06:51:40 +00:00
MarlinFirmware/Marlin/src/HAL/HAL_LPC1768/SoftwareSPI.cpp

91 lines
2.7 KiB
C++
Raw Normal View History

/**
* Marlin 3D Printer Firmware
* Copyright (C) 2016, 2017 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
*
* Based on Sprinter and grbl.
* Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
/**
* Software SPI functions originally from Arduino Sd2Card Library
* Copyright (C) 2009 by William Greiman
*/
/**
* For TARGET_LPC1768
*/
2018-02-04 02:25:57 +00:00
#include "../../inc/MarlinConfig.h"
#ifdef TARGET_LPC1768
// --------------------------------------------------------------------------
// Software SPI
// --------------------------------------------------------------------------
/**
* This software SPI runs at multiple rates. The SD software provides an index
* (spiRate) of 0-6. The mapping is:
* 0 - about 5 MHz peak (6 MHz on LPC1769)
* 1-2 - about 2 MHz peak
* 3 - about 1 MHz peak
* 4 - about 500 kHz peak
* 5 - about 250 kHz peak
* 6 - about 125 kHz peak
*/
2018-02-04 02:25:57 +00:00
uint8_t swSpiTransfer(uint8_t b, const uint8_t spi_speed, const pin_t sck_pin, const pin_t miso_pin, const pin_t mosi_pin) {
for (uint8_t i = 0; i < 8; i++) {
if (spi_speed == 0) {
2018-02-04 02:25:57 +00:00
WRITE(mosi_pin, !!(b & 0x80));
WRITE(sck_pin, HIGH);
b <<= 1;
2018-02-04 02:25:57 +00:00
if (miso_pin >= 0 && READ(miso_pin)) b |= 1;
WRITE(sck_pin, LOW);
}
else {
2018-02-04 02:25:57 +00:00
const uint8_t state = (b & 0x80) ? HIGH : LOW;
for (uint8_t j = 0; j < spi_speed; j++)
WRITE(mosi_pin, state);
for (uint8_t j = 0; j < spi_speed + (miso_pin >= 0 ? 0 : 1); j++)
WRITE(sck_pin, HIGH);
2018-02-04 02:05:23 +00:00
b <<= 1;
2018-02-04 02:25:57 +00:00
if (miso_pin >= 0 && READ(miso_pin)) b |= 1;
for (uint8_t j = 0; j < spi_speed; j++)
WRITE(sck_pin, LOW);
}
}
return b;
}
2018-02-04 02:25:57 +00:00
void swSpiBegin(const pin_t sck_pin, const pin_t miso_pin, const pin_t mosi_pin) {
SET_OUTPUT(sck_pin);
2018-02-04 02:25:57 +00:00
if (VALID_PIN(miso_pin)) SET_INPUT(miso_pin);
SET_OUTPUT(mosi_pin);
}
2018-02-04 02:25:57 +00:00
uint8_t swSpiInit(const uint8_t spiRate, const pin_t sck_pin, const pin_t mosi_pin) {
WRITE(mosi_pin, HIGH);
WRITE(sck_pin, LOW);
2018-02-04 02:25:57 +00:00
return (SystemCoreClock == 120000000 ? 44 : 38) / POW(2, 6 - min(spiRate, 6));
}
#endif // TARGET_LPC1768