Johannes Stratmann / mbed-dev

added prescaler for 16 bit pwm in LPC1347 target

Fork of mbed-dev by mbed official

api/SPISlave.h@147:ba84b7dc41a7, 2016-09-10 (annotated)

Committer:
JojoS
Date:
Sat Sep 10 15:32:04 2016 +0000
Revision:
147:ba84b7dc41a7
Parent:
144:ef7eb2e8f9f7 
added prescaler for 16 bit timers (solution as in LPC11xx), default prescaler 31 for max 28 ms period time

Who changed what in which revision?

UserRevisionLine numberNew contents of line
<> 144:ef7eb2e8f9f7 1 /* mbed Microcontroller Library
<> 144:ef7eb2e8f9f7 2 * Copyright (c) 2006-2013 ARM Limited
<> 144:ef7eb2e8f9f7 3 *
<> 144:ef7eb2e8f9f7 4 * Licensed under the Apache License, Version 2.0 (the "License");
<> 144:ef7eb2e8f9f7 5 * you may not use this file except in compliance with the License.
<> 144:ef7eb2e8f9f7 6 * You may obtain a copy of the License at
<> 144:ef7eb2e8f9f7 7 *
<> 144:ef7eb2e8f9f7 8 * http://www.apache.org/licenses/LICENSE-2.0
<> 144:ef7eb2e8f9f7 9 *
<> 144:ef7eb2e8f9f7 10 * Unless required by applicable law or agreed to in writing, software
<> 144:ef7eb2e8f9f7 11 * distributed under the License is distributed on an "AS IS" BASIS,
<> 144:ef7eb2e8f9f7 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
<> 144:ef7eb2e8f9f7 13 * See the License for the specific language governing permissions and
<> 144:ef7eb2e8f9f7 14 * limitations under the License.
<> 144:ef7eb2e8f9f7 15 */
<> 144:ef7eb2e8f9f7 16 #ifndef MBED_SPISLAVE_H
<> 144:ef7eb2e8f9f7 17 #define MBED_SPISLAVE_H
<> 144:ef7eb2e8f9f7 18
<> 144:ef7eb2e8f9f7 19 #include "platform.h"
<> 144:ef7eb2e8f9f7 20
<> 144:ef7eb2e8f9f7 21 #if DEVICE_SPISLAVE
<> 144:ef7eb2e8f9f7 22
<> 144:ef7eb2e8f9f7 23 #include "spi_api.h"
<> 144:ef7eb2e8f9f7 24
<> 144:ef7eb2e8f9f7 25 namespace mbed {
<> 144:ef7eb2e8f9f7 26
<> 144:ef7eb2e8f9f7 27 /** A SPI slave, used for communicating with a SPI Master device
<> 144:ef7eb2e8f9f7 28 *
<> 144:ef7eb2e8f9f7 29 * The default format is set to 8-bits, mode 0, and a clock frequency of 1MHz
<> 144:ef7eb2e8f9f7 30 *
<> 144:ef7eb2e8f9f7 31 * @Note Synchronization level: Not protected
<> 144:ef7eb2e8f9f7 32 *
<> 144:ef7eb2e8f9f7 33 * Example:
<> 144:ef7eb2e8f9f7 34 * @code
<> 144:ef7eb2e8f9f7 35 * // Reply to a SPI master as slave
<> 144:ef7eb2e8f9f7 36 *
<> 144:ef7eb2e8f9f7 37 * #include "mbed.h"
<> 144:ef7eb2e8f9f7 38 *
<> 144:ef7eb2e8f9f7 39 * SPISlave device(p5, p6, p7, p8); // mosi, miso, sclk, ssel
<> 144:ef7eb2e8f9f7 40 *
<> 144:ef7eb2e8f9f7 41 * int main() {
<> 144:ef7eb2e8f9f7 42 * device.reply(0x00); // Prime SPI with first reply
<> 144:ef7eb2e8f9f7 43 * while(1) {
<> 144:ef7eb2e8f9f7 44 * if(device.receive()) {
<> 144:ef7eb2e8f9f7 45 * int v = device.read(); // Read byte from master
<> 144:ef7eb2e8f9f7 46 * v = (v + 1) % 0x100; // Add one to it, modulo 256
<> 144:ef7eb2e8f9f7 47 * device.reply(v); // Make this the next reply
<> 144:ef7eb2e8f9f7 48 * }
<> 144:ef7eb2e8f9f7 49 * }
<> 144:ef7eb2e8f9f7 50 * }
<> 144:ef7eb2e8f9f7 51 * @endcode
<> 144:ef7eb2e8f9f7 52 */
<> 144:ef7eb2e8f9f7 53 class SPISlave {
<> 144:ef7eb2e8f9f7 54
<> 144:ef7eb2e8f9f7 55 public:
<> 144:ef7eb2e8f9f7 56
<> 144:ef7eb2e8f9f7 57 /** Create a SPI slave connected to the specified pins
<> 144:ef7eb2e8f9f7 58 *
<> 144:ef7eb2e8f9f7 59 * mosi or miso can be specfied as NC if not used
<> 144:ef7eb2e8f9f7 60 *
<> 144:ef7eb2e8f9f7 61 * @param mosi SPI Master Out, Slave In pin
<> 144:ef7eb2e8f9f7 62 * @param miso SPI Master In, Slave Out pin
<> 144:ef7eb2e8f9f7 63 * @param sclk SPI Clock pin
<> 144:ef7eb2e8f9f7 64 * @param ssel SPI chip select pin
<> 144:ef7eb2e8f9f7 65 */
<> 144:ef7eb2e8f9f7 66 SPISlave(PinName mosi, PinName miso, PinName sclk, PinName ssel);
<> 144:ef7eb2e8f9f7 67
<> 144:ef7eb2e8f9f7 68 /** Configure the data transmission format
<> 144:ef7eb2e8f9f7 69 *
<> 144:ef7eb2e8f9f7 70 * @param bits Number of bits per SPI frame (4 - 16)
<> 144:ef7eb2e8f9f7 71 * @param mode Clock polarity and phase mode (0 - 3)
<> 144:ef7eb2e8f9f7 72 *
<> 144:ef7eb2e8f9f7 73 * @code
<> 144:ef7eb2e8f9f7 74 * mode | POL PHA
<> 144:ef7eb2e8f9f7 75 * -----+--------
<> 144:ef7eb2e8f9f7 76 * 0 | 0 0
<> 144:ef7eb2e8f9f7 77 * 1 | 0 1
<> 144:ef7eb2e8f9f7 78 * 2 | 1 0
<> 144:ef7eb2e8f9f7 79 * 3 | 1 1
<> 144:ef7eb2e8f9f7 80 * @endcode
<> 144:ef7eb2e8f9f7 81 */
<> 144:ef7eb2e8f9f7 82 void format(int bits, int mode = 0);
<> 144:ef7eb2e8f9f7 83
<> 144:ef7eb2e8f9f7 84 /** Set the spi bus clock frequency
<> 144:ef7eb2e8f9f7 85 *
<> 144:ef7eb2e8f9f7 86 * @param hz SCLK frequency in hz (default = 1MHz)
<> 144:ef7eb2e8f9f7 87 */
<> 144:ef7eb2e8f9f7 88 void frequency(int hz = 1000000);
<> 144:ef7eb2e8f9f7 89
<> 144:ef7eb2e8f9f7 90 /** Polls the SPI to see if data has been received
<> 144:ef7eb2e8f9f7 91 *
<> 144:ef7eb2e8f9f7 92 * @returns
<> 144:ef7eb2e8f9f7 93 * 0 if no data,
<> 144:ef7eb2e8f9f7 94 * 1 otherwise
<> 144:ef7eb2e8f9f7 95 */
<> 144:ef7eb2e8f9f7 96 int receive(void);
<> 144:ef7eb2e8f9f7 97
<> 144:ef7eb2e8f9f7 98 /** Retrieve data from receive buffer as slave
<> 144:ef7eb2e8f9f7 99 *
<> 144:ef7eb2e8f9f7 100 * @returns
<> 144:ef7eb2e8f9f7 101 * the data in the receive buffer
<> 144:ef7eb2e8f9f7 102 */
<> 144:ef7eb2e8f9f7 103 int read(void);
<> 144:ef7eb2e8f9f7 104
<> 144:ef7eb2e8f9f7 105 /** Fill the transmission buffer with the value to be written out
<> 144:ef7eb2e8f9f7 106 * as slave on the next received message from the master.
<> 144:ef7eb2e8f9f7 107 *
<> 144:ef7eb2e8f9f7 108 * @param value the data to be transmitted next
<> 144:ef7eb2e8f9f7 109 */
<> 144:ef7eb2e8f9f7 110 void reply(int value);
<> 144:ef7eb2e8f9f7 111
<> 144:ef7eb2e8f9f7 112 protected:
<> 144:ef7eb2e8f9f7 113 spi_t _spi;
<> 144:ef7eb2e8f9f7 114
<> 144:ef7eb2e8f9f7 115 int _bits;
<> 144:ef7eb2e8f9f7 116 int _mode;
<> 144:ef7eb2e8f9f7 117 int _hz;
<> 144:ef7eb2e8f9f7 118 };
<> 144:ef7eb2e8f9f7 119
<> 144:ef7eb2e8f9f7 120 } // namespace mbed
<> 144:ef7eb2e8f9f7 121
<> 144:ef7eb2e8f9f7 122 #endif
<> 144:ef7eb2e8f9f7 123
<> 144:ef7eb2e8f9f7 124 #endif