Joshua Slater / BLE_API2

my version with changed conversion between duration units

Fork of BLE_API by Bluetooth Low Energy

ble/services/UARTService.h@758:85c13328a10a, 2015-08-05 (annotated)

Committer:
jslater8
Date:
Wed Aug 05 14:20:04 2015 +0000
Revision:
758:85c13328a10a
Parent:
728:997ba5e7b3b6 
Conversion from Interval duration units to milliseconds now in GapAdvertisingParams.h and changed getInterval to properly convert back to milliseconds

Who changed what in which revision?

UserRevisionLine numberNew contents of line
rgrover1 712:b04b5db36865 1 /* mbed Microcontroller Library
rgrover1 712:b04b5db36865 2 * Copyright (c) 2006-2013 ARM Limited
rgrover1 712:b04b5db36865 3 *
rgrover1 712:b04b5db36865 4 * Licensed under the Apache License, Version 2.0 (the "License");
rgrover1 712:b04b5db36865 5 * you may not use this file except in compliance with the License.
rgrover1 712:b04b5db36865 6 * You may obtain a copy of the License at
rgrover1 712:b04b5db36865 7 *
rgrover1 712:b04b5db36865 8 * http://www.apache.org/licenses/LICENSE-2.0
rgrover1 712:b04b5db36865 9 *
rgrover1 712:b04b5db36865 10 * Unless required by applicable law or agreed to in writing, software
rgrover1 712:b04b5db36865 11 * distributed under the License is distributed on an "AS IS" BASIS,
rgrover1 712:b04b5db36865 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
rgrover1 712:b04b5db36865 13 * See the License for the specific language governing permissions and
rgrover1 712:b04b5db36865 14 * limitations under the License.
rgrover1 712:b04b5db36865 15 */
rgrover1 712:b04b5db36865 16
rgrover1 712:b04b5db36865 17 #ifndef __BLE_UART_SERVICE_H__
rgrover1 712:b04b5db36865 18 #define __BLE_UART_SERVICE_H__
rgrover1 712:b04b5db36865 19
rgrover1 712:b04b5db36865 20 #include "mbed.h"
rgrover1 712:b04b5db36865 21 #include "Stream.h"
rgrover1 712:b04b5db36865 22
rgrover1 712:b04b5db36865 23 #include "ble/UUID.h"
rgrover1 712:b04b5db36865 24 #include "ble/BLE.h"
rgrover1 712:b04b5db36865 25
rgrover1 712:b04b5db36865 26 extern const uint8_t UARTServiceBaseUUID[UUID::LENGTH_OF_LONG_UUID];
rgrover1 712:b04b5db36865 27 extern const uint16_t UARTServiceShortUUID;
rgrover1 712:b04b5db36865 28 extern const uint16_t UARTServiceTXCharacteristicShortUUID;
rgrover1 712:b04b5db36865 29 extern const uint16_t UARTServiceRXCharacteristicShortUUID;
rgrover1 712:b04b5db36865 30
rgrover1 712:b04b5db36865 31 extern const uint8_t UARTServiceUUID[UUID::LENGTH_OF_LONG_UUID];
rgrover1 712:b04b5db36865 32 extern const uint8_t UARTServiceUUID_reversed[UUID::LENGTH_OF_LONG_UUID];
rgrover1 712:b04b5db36865 33
rgrover1 712:b04b5db36865 34 extern const uint8_t UARTServiceTXCharacteristicUUID[UUID::LENGTH_OF_LONG_UUID];
rgrover1 712:b04b5db36865 35 extern const uint8_t UARTServiceRXCharacteristicUUID[UUID::LENGTH_OF_LONG_UUID];
rgrover1 712:b04b5db36865 36
rgrover1 712:b04b5db36865 37 /**
rgrover1 712:b04b5db36865 38 * @class UARTService
rgrover1 712:b04b5db36865 39 * @brief BLE Service to enable UART over BLE
rgrover1 712:b04b5db36865 40 */
rgrover1 712:b04b5db36865 41 class UARTService {
rgrover1 712:b04b5db36865 42 public:
rgrover1 712:b04b5db36865 43 /**< Maximum length of data (in bytes) that can be transmitted by the UART service module to the peer. */
rgrover1 728:997ba5e7b3b6 44 static const unsigned BLE_UART_SERVICE_MAX_DATA_LEN = (BLE_GATT_MTU_SIZE_DEFAULT - 3);
rgrover1 712:b04b5db36865 45
rgrover1 712:b04b5db36865 46 public:
rgrover1 712:b04b5db36865 47
rgrover1 712:b04b5db36865 48 /**
rgrover1 712:b04b5db36865 49 * @param[ref] ble
rgrover1 712:b04b5db36865 50 * BLE object for the underlying controller.
rgrover1 712:b04b5db36865 51 */
rgrover1 712:b04b5db36865 52 UARTService(BLE &_ble) :
rgrover1 712:b04b5db36865 53 ble(_ble),
rgrover1 712:b04b5db36865 54 receiveBuffer(),
rgrover1 712:b04b5db36865 55 sendBuffer(),
rgrover1 712:b04b5db36865 56 sendBufferIndex(0),
rgrover1 712:b04b5db36865 57 numBytesReceived(0),
rgrover1 712:b04b5db36865 58 receiveBufferIndex(0),
rgrover1 712:b04b5db36865 59 txCharacteristic(UARTServiceTXCharacteristicUUID, receiveBuffer, 1, BLE_UART_SERVICE_MAX_DATA_LEN,
rgrover1 712:b04b5db36865 60 GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE_WITHOUT_RESPONSE),
rgrover1 712:b04b5db36865 61 rxCharacteristic(UARTServiceRXCharacteristicUUID, sendBuffer, 1, BLE_UART_SERVICE_MAX_DATA_LEN, GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_NOTIFY) {
rgrover1 712:b04b5db36865 62 GattCharacteristic *charTable[] = {&txCharacteristic, &rxCharacteristic};
rgrover1 712:b04b5db36865 63 GattService uartService(UARTServiceUUID, charTable, sizeof(charTable) / sizeof(GattCharacteristic *));
rgrover1 712:b04b5db36865 64
rgrover1 712:b04b5db36865 65 ble.addService(uartService);
rgrover1 712:b04b5db36865 66 ble.onDataWritten(this, &UARTService::onDataWritten);
rgrover1 712:b04b5db36865 67 }
rgrover1 712:b04b5db36865 68
rgrover1 712:b04b5db36865 69 /**
rgrover1 712:b04b5db36865 70 * Note: TX and RX characteristics are to be interpreted from the viewpoint of the GATT client using this service.
rgrover1 712:b04b5db36865 71 */
rgrover1 712:b04b5db36865 72 uint16_t getTXCharacteristicHandle() {
rgrover1 712:b04b5db36865 73 return txCharacteristic.getValueAttribute().getHandle();
rgrover1 712:b04b5db36865 74 }
rgrover1 712:b04b5db36865 75
rgrover1 712:b04b5db36865 76 /**
rgrover1 712:b04b5db36865 77 * Note: TX and RX characteristics are to be interpreted from the viewpoint of the GATT client using this service.
rgrover1 712:b04b5db36865 78 */
rgrover1 712:b04b5db36865 79 uint16_t getRXCharacteristicHandle() {
rgrover1 712:b04b5db36865 80 return rxCharacteristic.getValueAttribute().getHandle();
rgrover1 712:b04b5db36865 81 }
rgrover1 712:b04b5db36865 82
rgrover1 712:b04b5db36865 83 /**
rgrover1 712:b04b5db36865 84 * We attempt to collect bytes before pushing them to the UART RX
rgrover1 712:b04b5db36865 85 * characteristic--writing to the RX characteristic will then generate
rgrover1 712:b04b5db36865 86 * notifications for the client. Updates made in quick succession to a
rgrover1 712:b04b5db36865 87 * notification-generating characteristic will result in data being buffered
rgrover1 712:b04b5db36865 88 * in the bluetooth stack as notifications are sent out. The stack will have
rgrover1 712:b04b5db36865 89 * its limits for this buffering; typically a small number under 10.
rgrover1 712:b04b5db36865 90 * Collecting data into the sendBuffer buffer helps mitigate the rate of
rgrover1 712:b04b5db36865 91 * updates. But we shouldn't buffer a large amount of data before updating
rgrover1 712:b04b5db36865 92 * the characteristic otherwise the client will need to turn around and make
rgrover1 712:b04b5db36865 93 * a long read request; this is because notifications include only the first
rgrover1 712:b04b5db36865 94 * 20 bytes of the updated data.
rgrover1 712:b04b5db36865 95 *
rgrover1 712:b04b5db36865 96 * @param buffer The received update
rgrover1 712:b04b5db36865 97 * @param length Amount of characters to be appended.
rgrover1 712:b04b5db36865 98 * @return Amount of characters appended to the rxCharacteristic.
rgrover1 712:b04b5db36865 99 */
rgrover1 712:b04b5db36865 100 size_t write(const void *_buffer, size_t length) {
rgrover1 712:b04b5db36865 101 size_t origLength = length;
rgrover1 712:b04b5db36865 102 const uint8_t *buffer = static_cast<const uint8_t *>(_buffer);
rgrover1 712:b04b5db36865 103
rgrover1 712:b04b5db36865 104 if (ble.getGapState().connected) {
rgrover1 712:b04b5db36865 105 unsigned bufferIndex = 0;
rgrover1 712:b04b5db36865 106 while (length) {
rgrover1 712:b04b5db36865 107 unsigned bytesRemainingInSendBuffer = BLE_UART_SERVICE_MAX_DATA_LEN - sendBufferIndex;
rgrover1 712:b04b5db36865 108 unsigned bytesToCopy = (length < bytesRemainingInSendBuffer) ? length : bytesRemainingInSendBuffer;
rgrover1 712:b04b5db36865 109
rgrover1 712:b04b5db36865 110 /* copy bytes into sendBuffer */
rgrover1 712:b04b5db36865 111 memcpy(&sendBuffer[sendBufferIndex], &buffer[bufferIndex], bytesToCopy);
rgrover1 712:b04b5db36865 112 length -= bytesToCopy;
rgrover1 712:b04b5db36865 113 sendBufferIndex += bytesToCopy;
rgrover1 712:b04b5db36865 114 bufferIndex += bytesToCopy;
rgrover1 712:b04b5db36865 115
rgrover1 712:b04b5db36865 116 /* have we collected enough? */
rgrover1 712:b04b5db36865 117 if ((sendBufferIndex == BLE_UART_SERVICE_MAX_DATA_LEN) ||
rgrover1 712:b04b5db36865 118 // (sendBuffer[sendBufferIndex - 1] == '\r') ||
rgrover1 712:b04b5db36865 119 (sendBuffer[sendBufferIndex - 1] == '\n')) {
rgrover1 728:997ba5e7b3b6 120 ble.gattServer().write(getRXCharacteristicHandle(), static_cast<const uint8_t *>(sendBuffer), sendBufferIndex);
rgrover1 712:b04b5db36865 121 sendBufferIndex = 0;
rgrover1 712:b04b5db36865 122 }
rgrover1 712:b04b5db36865 123 }
rgrover1 712:b04b5db36865 124 }
rgrover1 712:b04b5db36865 125
rgrover1 712:b04b5db36865 126 return origLength;
rgrover1 712:b04b5db36865 127 }
rgrover1 712:b04b5db36865 128
rgrover1 712:b04b5db36865 129 /**
rgrover1 712:b04b5db36865 130 * Helper function to write out strings.
rgrover1 712:b04b5db36865 131 * @param str The received string.
rgrover1 712:b04b5db36865 132 * @return Amount of characters appended to the rxCharacteristic.
rgrover1 712:b04b5db36865 133 */
rgrover1 712:b04b5db36865 134 size_t writeString(const char *str) {
rgrover1 712:b04b5db36865 135 return write(str, strlen(str));
rgrover1 712:b04b5db36865 136 }
rgrover1 712:b04b5db36865 137
rgrover1 712:b04b5db36865 138 /**
rgrover1 712:b04b5db36865 139 * Override for Stream::_putc()
rgrover1 712:b04b5db36865 140 * @param c
rgrover1 712:b04b5db36865 141 * This function writes the character c, cast to an unsigned char, to stream.
rgrover1 712:b04b5db36865 142 * @return
rgrover1 712:b04b5db36865 143 * The character written as an unsigned char cast to an int or EOF on error.
rgrover1 712:b04b5db36865 144 */
rgrover1 712:b04b5db36865 145 int _putc(int c) {
rgrover1 712:b04b5db36865 146 return (write(&c, 1) == 1) ? 1 : EOF;
rgrover1 712:b04b5db36865 147 }
rgrover1 712:b04b5db36865 148
rgrover1 712:b04b5db36865 149 /**
rgrover1 712:b04b5db36865 150 * Override for Stream::_getc()
rgrover1 712:b04b5db36865 151 * @return
rgrover1 712:b04b5db36865 152 * The character read.
rgrover1 712:b04b5db36865 153 */
rgrover1 712:b04b5db36865 154 int _getc() {
rgrover1 712:b04b5db36865 155 if (receiveBufferIndex == numBytesReceived) {
rgrover1 712:b04b5db36865 156 return EOF;
rgrover1 712:b04b5db36865 157 }
rgrover1 712:b04b5db36865 158
rgrover1 712:b04b5db36865 159 return receiveBuffer[receiveBufferIndex++];
rgrover1 712:b04b5db36865 160 }
rgrover1 712:b04b5db36865 161
rgrover1 728:997ba5e7b3b6 162 protected:
rgrover1 712:b04b5db36865 163 /**
rgrover1 712:b04b5db36865 164 * This callback allows the UART service to receive updates to the
rgrover1 712:b04b5db36865 165 * txCharacteristic. The application should forward the call to this
rgrover1 712:b04b5db36865 166 * function from the global onDataWritten() callback handler; or if that's
rgrover1 712:b04b5db36865 167 * not used, this method can be used as a callback directly.
rgrover1 712:b04b5db36865 168 */
rgrover1 712:b04b5db36865 169 void onDataWritten(const GattWriteCallbackParams *params) {
rgrover1 712:b04b5db36865 170 if (params->handle == getTXCharacteristicHandle()) {
rgrover1 712:b04b5db36865 171 uint16_t bytesRead = params->len;
rgrover1 712:b04b5db36865 172 if (bytesRead <= BLE_UART_SERVICE_MAX_DATA_LEN) {
rgrover1 712:b04b5db36865 173 numBytesReceived = bytesRead;
rgrover1 712:b04b5db36865 174 receiveBufferIndex = 0;
rgrover1 712:b04b5db36865 175 memcpy(receiveBuffer, params->data, numBytesReceived);
rgrover1 712:b04b5db36865 176 }
rgrover1 712:b04b5db36865 177 }
rgrover1 712:b04b5db36865 178 }
rgrover1 712:b04b5db36865 179
rgrover1 728:997ba5e7b3b6 180 protected:
rgrover1 712:b04b5db36865 181 BLE &ble;
rgrover1 712:b04b5db36865 182
rgrover1 712:b04b5db36865 183 uint8_t receiveBuffer[BLE_UART_SERVICE_MAX_DATA_LEN]; /**< The local buffer into which we receive
rgrover1 712:b04b5db36865 184 * inbound data before forwarding it to the
rgrover1 712:b04b5db36865 185 * application. */
rgrover1 712:b04b5db36865 186
rgrover1 712:b04b5db36865 187 uint8_t sendBuffer[BLE_UART_SERVICE_MAX_DATA_LEN]; /**< The local buffer into which outbound data is
rgrover1 712:b04b5db36865 188 * accumulated before being pushed to the
rgrover1 712:b04b5db36865 189 * rxCharacteristic. */
rgrover1 712:b04b5db36865 190 uint8_t sendBufferIndex;
rgrover1 712:b04b5db36865 191 uint8_t numBytesReceived;
rgrover1 712:b04b5db36865 192 uint8_t receiveBufferIndex;
rgrover1 712:b04b5db36865 193
rgrover1 712:b04b5db36865 194 GattCharacteristic txCharacteristic; /**< From the point of view of the external client, this is the characteristic
rgrover1 712:b04b5db36865 195 * they'd write into in order to communicate with this application. */
rgrover1 712:b04b5db36865 196 GattCharacteristic rxCharacteristic; /**< From the point of view of the external client, this is the characteristic
rgrover1 712:b04b5db36865 197 * they'd read from in order to receive the bytes transmitted by this
rgrover1 712:b04b5db36865 198 * application. */
rgrover1 712:b04b5db36865 199 };
rgrover1 712:b04b5db36865 200
rgrover1 712:b04b5db36865 201 #endif /* #ifndef __BLE_UART_SERVICE_H__*/