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-rw-r--r--Makefile1
-rw-r--r--core/comm/HardwareSPI.cpp129
-rw-r--r--core/comm/HardwareSPI.h57
-rw-r--r--libmaple/spi.h11
4 files changed, 197 insertions, 1 deletions
diff --git a/Makefile b/Makefile
index 8d441a0..e7df3a5 100644
--- a/Makefile
+++ b/Makefile
@@ -83,6 +83,7 @@ CPPSRC = core/wiring_math.cpp \
core/Print.cpp \
core/comm/HardwareSerial.cpp \
core/comm/HardwareUsb.cpp \
+ core/comm/HardwareSPI.cpp \
main.cpp
# i really have no idea what i'm doing
diff --git a/core/comm/HardwareSPI.cpp b/core/comm/HardwareSPI.cpp
new file mode 100644
index 0000000..542742b
--- /dev/null
+++ b/core/comm/HardwareSPI.cpp
@@ -0,0 +1,129 @@
+/* *****************************************************************************
+ * The MIT License
+ *
+ * Copyright (c) 2010 Perry Hung.
+ *
+ * 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.
+ * ****************************************************************************/
+
+/**
+ * @brief HardwareSPI "wiring-like" api for SPI
+ */
+
+/* Speeds:
+ * -----------------------------------
+ * Interface num: SPI1 SPI2
+ * Bus APB2 APB1
+ * -----------------------------------
+ * Prescaler Frequencies
+ * -----------------------------------
+ * 2: N/A 18 000 000
+ * 4: 18 000 000 9 000 000
+ * 8: 9 000 000 4 500 000
+ * 16: 4 500 000 2 250 000
+ * 32: 2 250 000 1 125 000
+ * 64: 1 125 000 562 500
+ * 128: 562 500 281 250
+ * 256: 281 250 140 625
+ * */
+
+#include "wiring.h"
+#include "spi.h"
+#include "HardwareSPI.h"
+
+static const uint32 prescaleFactors[MAX_SPI_FREQS] = {
+ SPI_PRESCALE_2, // SPI_18MHZ
+ SPI_PRESCALE_4, // SPI_9MHZ
+ SPI_PRESCALE_8, // SPI_4_5MHZ
+ SPI_PRESCALE_16, // SPI_2_25MHZ
+ SPI_PRESCALE_32, // SPI_1_125MHZ
+ SPI_PRESCALE_64, // SPI_562_500KHZ
+ SPI_PRESCALE_128, // SPI_281_250KHZ
+ SPI_PRESCALE_256, // SPI_140_625KHZ
+};
+
+
+/**
+ * @brief Initialize a SPI peripheral
+ * @param freq frequency to run at, must one of the following values:
+ * - SPI_18MHZ
+ * - SPI_9MHZ
+ * - SPI_4_5MHZ
+ * - SPI_2_25MHZ
+ * - SPI_1_125MHZ
+ * - SPI_562_500KHZ
+ * - SPI_281_250KHZ
+ * - SPI_140_625KHZ
+ * @param endianness endianness of the data frame, must be either LSBFIRST
+ * or MSBFIRST
+ * @param mode SPI standard CPOL and CPHA levels
+ */
+void HardwareSPI::begin(SPIFrequency freq, uint32 endianness, uint32 mode) {
+ uint32 spi_num = this->spi_num;
+ uint32 high_speed = 0;
+ uint32 index;
+ uint32 prescale;
+
+ if ((freq >= MAX_SPI_FREQS) ||
+ !((endianness == LSBFIRST) ||
+ (endianness == MSBFIRST)) ||
+ (mode >= 4)) {
+ return;
+ }
+
+ /* SPI1 is too fast for 140625 */
+ if ((spi_num == 1) && (freq == SPI_140_625KHZ)) {
+ return;
+ }
+
+ endianness = (endianness == LSBFIRST) ? SPI_LSBFIRST : SPI_MSBFIRST;
+ prescale = (spi_num == 1) ? prescaleFactors[freq + 1] : prescaleFactors[freq];
+
+ spi_init(spi_num, prescale, endianness, 0);
+}
+
+/**
+ * @brief Initialize a SPI peripheral with a default speed of 1.125 MHZ, MSBFIRST,
+ * mode 0
+ * @param mode SPI standard CPOL and CPHA levels
+ */
+void HardwareSPI::begin(void) {
+ begin(SPI_1_125MHZ, MSBFIRST, 0);
+}
+
+/**
+ * @brief send a byte out the spi peripheral
+ * @param data byte to send
+ */
+void HardwareSPI::send(uint8 data) {
+ spi_tx(this->spi_num, data);
+}
+
+
+/**
+ * @brief read a byte from the spi peripheral
+ * @return byte in the buffer
+ */
+uint8 HardwareSPI::recv(void) {
+ return spi_rx(this->spi_num);
+}
+
+HardwareSPI::HardwareSPI(uint32 spi_num) {
+ this->spi_num = spi_num;
+}
diff --git a/core/comm/HardwareSPI.h b/core/comm/HardwareSPI.h
new file mode 100644
index 0000000..b974334
--- /dev/null
+++ b/core/comm/HardwareSPI.h
@@ -0,0 +1,57 @@
+/* *****************************************************************************
+ * The MIT License
+ *
+ * Copyright (c) 2010 Perry Hung.
+ *
+ * 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.
+ * ****************************************************************************/
+
+/**
+ * @brief HardwareSPI definitions
+ */
+
+#ifndef _HARDWARESPI_H_
+#define _HARDWARESPI_H_
+
+typedef enum SPIFrequency {
+ SPI_18MHZ = 0,
+ SPI_9MHZ = 1,
+ SPI_4_5MHZ = 2,
+ SPI_2_25MHZ = 3,
+ SPI_1_125MHZ = 4,
+ SPI_562_500KHZ = 5,
+ SPI_281_250KHZ = 6,
+ SPI_140_625KHZ = 7,
+ MAX_SPI_FREQS = 8,
+} SPIFrequency;
+
+class HardwareSPI {
+ private:
+ uint32 spi_num;
+
+ public:
+ HardwareSPI(uint32 spi_num);
+ void begin(void);
+ void begin(SPIFrequency freq, uint32 endianness, uint32 mode);
+ void send(uint8 data);
+ uint8 recv(void);
+};
+
+#endif
+
diff --git a/libmaple/spi.h b/libmaple/spi.h
index 457f39b..cde3b42 100644
--- a/libmaple/spi.h
+++ b/libmaple/spi.h
@@ -48,7 +48,7 @@ extern "C" {
#define CR1_BR_PRESCALE_128 0x00000030
#define CR1_BR_PRESCALE_256 0x00000038
-#define CR1_LSBFIRST BIT(7 // data frame format
+#define CR1_LSBFIRST BIT(7) // data frame format
#define CR1_MSTR BIT(2) // master selection
#define CR1_SSM BIT(9) // software slave management
#define CR1_SSI BIT(8) // internal slave select
@@ -98,6 +98,15 @@ void spi_init(uint32 spi_num,
uint32 mode);
void spi_tx(uint32 spi_num, uint8 data);
+static inline uint8 spi_rx(uint32 spi_num) {
+ SPI *spi;
+
+ ASSERT(spi_num == 1 || spi_num == 2);
+ spi = (spi_num == 1) ? (SPI*)SPI1_BASE : (SPI*)SPI2_BASE;
+
+ return spi->DR;
+}
+
#ifdef __cplusplus
}
#endif