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Development branch of the mbed library sources. This library is kept in synch with the latest changes from the mbed SDK and it is not guaranteed to work.

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The official Mbed 2 C/C++ SDK provides the software platform and libraries to build your applications.

Last commit 20 Feb 2019 by mbed official

targets/hal/TARGET_Freescale/TARGET_KL05Z/spi_api.c@72:248c61396e08, 2014-01-13 (annotated)

Committer:
mbed_official
Date:
Mon Jan 13 10:45:05 2014 +0000
Revision:
72:248c61396e08
Parent:
20:4263a77256ae
Child:
78:2cab419ff388
Synchronized with git revision f1904ba15c06215a7530efd2d5a16c25af9d29ff



Full URL: https://github.com/mbedmicro/mbed/commit/f1904ba15c06215a7530efd2d5a16c25af9d29ff/



KL46Z: Added Sleep, LED3 and LED4 definitions, switches

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bogdanm 20:4263a77256ae 1 /* mbed Microcontroller Library
bogdanm 20:4263a77256ae 2 * Copyright (c) 2006-2013 ARM Limited
bogdanm 20:4263a77256ae 3 *
bogdanm 20:4263a77256ae 4 * Licensed under the Apache License, Version 2.0 (the "License");
bogdanm 20:4263a77256ae 5 * you may not use this file except in compliance with the License.
bogdanm 20:4263a77256ae 6 * You may obtain a copy of the License at
bogdanm 20:4263a77256ae 7 *
bogdanm 20:4263a77256ae 8 * http://www.apache.org/licenses/LICENSE-2.0
bogdanm 20:4263a77256ae 9 *
bogdanm 20:4263a77256ae 10 * Unless required by applicable law or agreed to in writing, software
bogdanm 20:4263a77256ae 11 * distributed under the License is distributed on an "AS IS" BASIS,
bogdanm 20:4263a77256ae 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
bogdanm 20:4263a77256ae 13 * See the License for the specific language governing permissions and
bogdanm 20:4263a77256ae 14 * limitations under the License.
bogdanm 20:4263a77256ae 15 */
bogdanm 20:4263a77256ae 16 #include "spi_api.h"
bogdanm 20:4263a77256ae 17
bogdanm 20:4263a77256ae 18 #include <math.h>
bogdanm 20:4263a77256ae 19
bogdanm 20:4263a77256ae 20 #include "cmsis.h"
bogdanm 20:4263a77256ae 21 #include "pinmap.h"
bogdanm 20:4263a77256ae 22 #include "error.h"
bogdanm 20:4263a77256ae 23
bogdanm 20:4263a77256ae 24 static const PinMap PinMap_SPI_SCLK[] = {
bogdanm 20:4263a77256ae 25 {PTB0, SPI_0, 3},
bogdanm 20:4263a77256ae 26 {NC , NC , 0}
bogdanm 20:4263a77256ae 27 };
bogdanm 20:4263a77256ae 28
bogdanm 20:4263a77256ae 29 static const PinMap PinMap_SPI_MOSI[] = {
bogdanm 20:4263a77256ae 30 {PTA7, SPI_0, 3},
bogdanm 20:4263a77256ae 31 {NC , NC , 0}
bogdanm 20:4263a77256ae 32 };
bogdanm 20:4263a77256ae 33
bogdanm 20:4263a77256ae 34 static const PinMap PinMap_SPI_MISO[] = {
bogdanm 20:4263a77256ae 35 {PTA6, SPI_0, 3},
bogdanm 20:4263a77256ae 36 {NC , NC , 0}
bogdanm 20:4263a77256ae 37 };
bogdanm 20:4263a77256ae 38
bogdanm 20:4263a77256ae 39 static const PinMap PinMap_SPI_SSEL[] = {
bogdanm 20:4263a77256ae 40 {PTA5, SPI_0, 3},
bogdanm 20:4263a77256ae 41 {NC , NC , 0}
bogdanm 20:4263a77256ae 42 };
bogdanm 20:4263a77256ae 43
bogdanm 20:4263a77256ae 44 void spi_init(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel) {
bogdanm 20:4263a77256ae 45 // determine the SPI to use
bogdanm 20:4263a77256ae 46 SPIName spi_mosi = (SPIName)pinmap_peripheral(mosi, PinMap_SPI_MOSI);
bogdanm 20:4263a77256ae 47 SPIName spi_miso = (SPIName)pinmap_peripheral(miso, PinMap_SPI_MISO);
bogdanm 20:4263a77256ae 48 SPIName spi_sclk = (SPIName)pinmap_peripheral(sclk, PinMap_SPI_SCLK);
bogdanm 20:4263a77256ae 49 SPIName spi_ssel = (SPIName)pinmap_peripheral(ssel, PinMap_SPI_SSEL);
bogdanm 20:4263a77256ae 50 SPIName spi_data = (SPIName)pinmap_merge(spi_mosi, spi_miso);
bogdanm 20:4263a77256ae 51 SPIName spi_cntl = (SPIName)pinmap_merge(spi_sclk, spi_ssel);
bogdanm 20:4263a77256ae 52
bogdanm 20:4263a77256ae 53 obj->spi = (SPI_Type*)pinmap_merge(spi_data, spi_cntl);
bogdanm 20:4263a77256ae 54 if ((int)obj->spi == NC) {
bogdanm 20:4263a77256ae 55 error("SPI pinout mapping failed");
bogdanm 20:4263a77256ae 56 }
bogdanm 20:4263a77256ae 57
bogdanm 20:4263a77256ae 58 // enable power and clocking
bogdanm 20:4263a77256ae 59 switch ((int)obj->spi) {
bogdanm 20:4263a77256ae 60 case SPI_0:
bogdanm 20:4263a77256ae 61 SIM->SCGC5 |= (SIM_SCGC5_PORTA_MASK | SIM_SCGC5_PORTB_MASK);
bogdanm 20:4263a77256ae 62 SIM->SCGC4 |= SIM_SCGC4_SPI0_MASK;
bogdanm 20:4263a77256ae 63 break;
bogdanm 20:4263a77256ae 64 }
bogdanm 20:4263a77256ae 65
bogdanm 20:4263a77256ae 66 // set default format and frequency
bogdanm 20:4263a77256ae 67 if (ssel == NC) {
bogdanm 20:4263a77256ae 68 spi_format(obj, 8, 0, 0); // 8 bits, mode 0, master
bogdanm 20:4263a77256ae 69 } else {
bogdanm 20:4263a77256ae 70 spi_format(obj, 8, 0, 1); // 8 bits, mode 0, slave
bogdanm 20:4263a77256ae 71 }
bogdanm 20:4263a77256ae 72 spi_frequency(obj, 1000000);
bogdanm 20:4263a77256ae 73
bogdanm 20:4263a77256ae 74 // enable SPI
bogdanm 20:4263a77256ae 75 obj->spi->C1 |= SPI_C1_SPE_MASK;
bogdanm 20:4263a77256ae 76
bogdanm 20:4263a77256ae 77 // pin out the spi pins
bogdanm 20:4263a77256ae 78 pinmap_pinout(mosi, PinMap_SPI_MOSI);
bogdanm 20:4263a77256ae 79 pinmap_pinout(miso, PinMap_SPI_MISO);
bogdanm 20:4263a77256ae 80 pinmap_pinout(sclk, PinMap_SPI_SCLK);
bogdanm 20:4263a77256ae 81 if (ssel != NC) {
bogdanm 20:4263a77256ae 82 pinmap_pinout(ssel, PinMap_SPI_SSEL);
bogdanm 20:4263a77256ae 83 }
bogdanm 20:4263a77256ae 84 }
bogdanm 20:4263a77256ae 85
bogdanm 20:4263a77256ae 86 void spi_free(spi_t *obj) {
bogdanm 20:4263a77256ae 87 // [TODO]
bogdanm 20:4263a77256ae 88 }
bogdanm 20:4263a77256ae 89 void spi_format(spi_t *obj, int bits, int mode, int slave) {
bogdanm 20:4263a77256ae 90 if (bits != 8) {
bogdanm 20:4263a77256ae 91 error("Only 8bits SPI supported");
bogdanm 20:4263a77256ae 92 }
bogdanm 20:4263a77256ae 93
bogdanm 20:4263a77256ae 94 if ((mode < 0) || (mode > 3)) {
bogdanm 20:4263a77256ae 95 error("SPI mode unsupported");
bogdanm 20:4263a77256ae 96 }
bogdanm 20:4263a77256ae 97
bogdanm 20:4263a77256ae 98 uint8_t polarity = (mode & 0x2) ? 1 : 0;
bogdanm 20:4263a77256ae 99 uint8_t phase = (mode & 0x1) ? 1 : 0;
bogdanm 20:4263a77256ae 100 uint8_t c1_data = ((!slave) << 4) | (polarity << 3) | (phase << 2);
bogdanm 20:4263a77256ae 101
bogdanm 20:4263a77256ae 102 // clear MSTR, CPOL and CPHA bits
bogdanm 20:4263a77256ae 103 obj->spi->C1 &= ~(0x7 << 2);
bogdanm 20:4263a77256ae 104
bogdanm 20:4263a77256ae 105 // write new value
bogdanm 20:4263a77256ae 106 obj->spi->C1 |= c1_data;
bogdanm 20:4263a77256ae 107 }
bogdanm 20:4263a77256ae 108
bogdanm 20:4263a77256ae 109 void spi_frequency(spi_t *obj, int hz) {
bogdanm 20:4263a77256ae 110 uint32_t error = 0;
bogdanm 20:4263a77256ae 111 uint32_t p_error = 0xffffffff;
bogdanm 20:4263a77256ae 112 uint32_t ref = 0;
bogdanm 20:4263a77256ae 113 uint8_t spr = 0;
bogdanm 20:4263a77256ae 114 uint8_t ref_spr = 0;
bogdanm 20:4263a77256ae 115 uint8_t ref_prescaler = 0;
bogdanm 20:4263a77256ae 116
bogdanm 20:4263a77256ae 117 // bus clk
mbed_official 72:248c61396e08 118 uint32_t PCLK = SystemCoreClock / (((SIM->CLKDIV1 & SIM_CLKDIV1_OUTDIV4_MASK) >> SIM_CLKDIV1_OUTDIV4_SHIFT) + 1);
bogdanm 20:4263a77256ae 119 uint8_t prescaler = 1;
bogdanm 20:4263a77256ae 120 uint8_t divisor = 2;
bogdanm 20:4263a77256ae 121
bogdanm 20:4263a77256ae 122 for (prescaler = 1; prescaler <= 8; prescaler++) {
bogdanm 20:4263a77256ae 123 divisor = 2;
bogdanm 20:4263a77256ae 124 for (spr = 0; spr <= 8; spr++) {
bogdanm 20:4263a77256ae 125 ref = PCLK / (prescaler*divisor);
bogdanm 20:4263a77256ae 126 error = (ref > hz) ? ref - hz : hz - ref;
bogdanm 20:4263a77256ae 127 if (error < p_error) {
bogdanm 20:4263a77256ae 128 ref_spr = spr;
bogdanm 20:4263a77256ae 129 ref_prescaler = prescaler - 1;
bogdanm 20:4263a77256ae 130 p_error = error;
bogdanm 20:4263a77256ae 131 }
bogdanm 20:4263a77256ae 132 divisor *= 2;
bogdanm 20:4263a77256ae 133 }
bogdanm 20:4263a77256ae 134 }
bogdanm 20:4263a77256ae 135
bogdanm 20:4263a77256ae 136 // set SPPR and SPR
bogdanm 20:4263a77256ae 137 obj->spi->BR = ((ref_prescaler & 0x7) << 4) | (ref_spr & 0xf);
bogdanm 20:4263a77256ae 138 }
bogdanm 20:4263a77256ae 139
bogdanm 20:4263a77256ae 140 static inline int spi_writeable(spi_t * obj) {
bogdanm 20:4263a77256ae 141 return (obj->spi->S & SPI_S_SPTEF_MASK) ? 1 : 0;
bogdanm 20:4263a77256ae 142 }
bogdanm 20:4263a77256ae 143
bogdanm 20:4263a77256ae 144 static inline int spi_readable(spi_t * obj) {
bogdanm 20:4263a77256ae 145 return (obj->spi->S & SPI_S_SPRF_MASK) ? 1 : 0;
bogdanm 20:4263a77256ae 146 }
bogdanm 20:4263a77256ae 147
bogdanm 20:4263a77256ae 148 int spi_master_write(spi_t *obj, int value) {
bogdanm 20:4263a77256ae 149 // wait tx buffer empty
bogdanm 20:4263a77256ae 150 while(!spi_writeable(obj));
bogdanm 20:4263a77256ae 151 obj->spi->D = (value & 0xff);
bogdanm 20:4263a77256ae 152
bogdanm 20:4263a77256ae 153 // wait rx buffer full
bogdanm 20:4263a77256ae 154 while (!spi_readable(obj));
bogdanm 20:4263a77256ae 155 return obj->spi->D & 0xff;
bogdanm 20:4263a77256ae 156 }
bogdanm 20:4263a77256ae 157
bogdanm 20:4263a77256ae 158 int spi_slave_receive(spi_t *obj) {
bogdanm 20:4263a77256ae 159 return spi_readable(obj);
bogdanm 20:4263a77256ae 160 }
bogdanm 20:4263a77256ae 161
bogdanm 20:4263a77256ae 162 int spi_slave_read(spi_t *obj) {
bogdanm 20:4263a77256ae 163 return obj->spi->D;
bogdanm 20:4263a77256ae 164 }
bogdanm 20:4263a77256ae 165
bogdanm 20:4263a77256ae 166 void spi_slave_write(spi_t *obj, int value) {
bogdanm 20:4263a77256ae 167 while (!spi_writeable(obj));
bogdanm 20:4263a77256ae 168 obj->spi->D = value;
bogdanm 20:4263a77256ae 169 }