Diff: mbed/SPI.h

Revision:

0:0dee8840a1c0

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed/SPI.h	Mon Jul 29 20:38:00 2019 +0000
@@ -0,0 +1,114 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2013 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef MBED_SPI_H
+#define MBED_SPI_H
+
+#include "platform.h"
+
+#if DEVICE_SPI
+
+#include "spi_api.h"
+
+namespace mbed {
+
+/** A SPI Master, used for communicating with SPI slave devices
+ *
+ * The default format is set to 8-bits, mode 0, and a clock frequency of 1MHz
+ *
+ * Most SPI devices will also require Chip Select and Reset signals. These
+ * can be controlled using <DigitalOut> pins
+ *
+ * Example:
+ * @code
+ * // Send a byte to a SPI slave, and record the response
+ *
+ * #include "mbed.h"
+ *
+ * SPI device(p5, p6, p7); // mosi, miso, sclk
+ *
+ * int main() {
+ *     int response = device.write(0xFF);
+ * }
+ * @endcode
+ */
+class SPI {
+
+public:
+
+    /** Create a SPI master connected to the specified pins
+     *
+     * Pin Options:
+     *  (5, 6, 7) or (11, 12, 13)
+     *
+     *  mosi or miso can be specfied as NC if not used
+     *
+     *  @param mosi SPI Master Out, Slave In pin
+     *  @param miso SPI Master In, Slave Out pin
+     *  @param sclk SPI Clock pin
+     */
+    SPI(PinName mosi, PinName miso, PinName sclk, PinName _unused=NC);
+
+    /** Configure the data transmission format
+     *
+     *  @param bits Number of bits per SPI frame (4 - 16)
+     *  @param mode Clock polarity and phase mode (0 - 3)
+     *
+     * @code
+     * mode | POL PHA
+     * -----+--------
+     *   0  |  0   0
+     *   1  |  0   1
+     *   2  |  1   0
+     *   3  |  1   1
+     * @endcode
+     */
+    void format(int bits, int mode = 0);
+
+    /** Set the spi bus clock frequency
+     *
+     *  @param hz SCLK frequency in hz (default = 1MHz)
+     */
+    void frequency(int hz = 1000000);
+
+    /** Write to the SPI Slave and return the response
+     *
+     *  @param value Data to be sent to the SPI slave
+     *
+     *  @returns
+     *    Response from the SPI slave
+    */
+    virtual int write(int value);
+
+public:
+    virtual ~SPI() {
+    }
+
+protected:
+    spi_t _spi;
+
+    void aquire(void);
+    static SPI *_owner;
+    int _bits;
+    int _mode;
+    int _hz;
+};
+
+} // namespace mbed
+
+#endif
+
+#endif
+