Martin Woolley / microbit-dal-bluetooth-mdw_starter

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source/drivers/MicroBitRadio.cpp@18:e2f92ac26450, 2016-07-13 (annotated)

Committer:
LancasterUniversity
Date:
Wed Jul 13 12:17:48 2016 +0100
Revision:
18:e2f92ac26450
Parent:
1:8aa5cdb4ab67
Child:
19:ebc07f856999
Synchronized with git rev a82254b9

Author: Joe Finney

microbit: MicroBitRadio support for multiple enable/disable operations



MicroBitRadio::disable neglected to reset the internal status flag indicating

that the radio has bene initialised, which prevent subsequent enable()

operations completing properly.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Jonathan Austin 1:8aa5cdb4ab67 1 /*
Jonathan Austin 1:8aa5cdb4ab67 2 The MIT License (MIT)
Jonathan Austin 1:8aa5cdb4ab67 3
Jonathan Austin 1:8aa5cdb4ab67 4 Copyright (c) 2016 British Broadcasting Corporation.
Jonathan Austin 1:8aa5cdb4ab67 5 This software is provided by Lancaster University by arrangement with the BBC.
Jonathan Austin 1:8aa5cdb4ab67 6
Jonathan Austin 1:8aa5cdb4ab67 7 Permission is hereby granted, free of charge, to any person obtaining a
Jonathan Austin 1:8aa5cdb4ab67 8 copy of this software and associated documentation files (the "Software"),
Jonathan Austin 1:8aa5cdb4ab67 9 to deal in the Software without restriction, including without limitation
Jonathan Austin 1:8aa5cdb4ab67 10 the rights to use, copy, modify, merge, publish, distribute, sublicense,
Jonathan Austin 1:8aa5cdb4ab67 11 and/or sell copies of the Software, and to permit persons to whom the
Jonathan Austin 1:8aa5cdb4ab67 12 Software is furnished to do so, subject to the following conditions:
Jonathan Austin 1:8aa5cdb4ab67 13
Jonathan Austin 1:8aa5cdb4ab67 14 The above copyright notice and this permission notice shall be included in
Jonathan Austin 1:8aa5cdb4ab67 15 all copies or substantial portions of the Software.
Jonathan Austin 1:8aa5cdb4ab67 16
Jonathan Austin 1:8aa5cdb4ab67 17 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
Jonathan Austin 1:8aa5cdb4ab67 18 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
Jonathan Austin 1:8aa5cdb4ab67 19 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
Jonathan Austin 1:8aa5cdb4ab67 20 THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
Jonathan Austin 1:8aa5cdb4ab67 21 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
Jonathan Austin 1:8aa5cdb4ab67 22 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
Jonathan Austin 1:8aa5cdb4ab67 23 DEALINGS IN THE SOFTWARE.
Jonathan Austin 1:8aa5cdb4ab67 24 */
Jonathan Austin 1:8aa5cdb4ab67 25
Jonathan Austin 1:8aa5cdb4ab67 26 #include "MicroBitConfig.h"
Jonathan Austin 1:8aa5cdb4ab67 27 #include "MicroBitRadio.h"
Jonathan Austin 1:8aa5cdb4ab67 28 #include "MicroBitComponent.h"
Jonathan Austin 1:8aa5cdb4ab67 29 #include "EventModel.h"
Jonathan Austin 1:8aa5cdb4ab67 30 #include "MicroBitDevice.h"
Jonathan Austin 1:8aa5cdb4ab67 31 #include "ErrorNo.h"
Jonathan Austin 1:8aa5cdb4ab67 32 #include "MicroBitFiber.h"
Jonathan Austin 1:8aa5cdb4ab67 33 #include "MicroBitBLEManager.h"
Jonathan Austin 1:8aa5cdb4ab67 34
Jonathan Austin 1:8aa5cdb4ab67 35 /**
Jonathan Austin 1:8aa5cdb4ab67 36 * Provides a simple broadcast radio abstraction, built upon the raw nrf51822 RADIO module.
Jonathan Austin 1:8aa5cdb4ab67 37 *
Jonathan Austin 1:8aa5cdb4ab67 38 * The nrf51822 RADIO module supports a number of proprietary modes of operation oher than the typical BLE usage.
Jonathan Austin 1:8aa5cdb4ab67 39 * This class uses one of these modes to enable simple, point to multipoint communication directly between micro:bits.
Jonathan Austin 1:8aa5cdb4ab67 40 *
Jonathan Austin 1:8aa5cdb4ab67 41 * TODO: The protocols implemented here do not currently perform any significant form of energy management,
Jonathan Austin 1:8aa5cdb4ab67 42 * which means that they will consume far more energy than their BLE equivalent. Later versions of the protocol
Jonathan Austin 1:8aa5cdb4ab67 43 * should look to address this through energy efficient broadcast techbiques / sleep scheduling. In particular, the GLOSSY
Jonathan Austin 1:8aa5cdb4ab67 44 * approach to efficient rebroadcast and network synchronisation would likely provide an effective future step.
Jonathan Austin 1:8aa5cdb4ab67 45 *
Jonathan Austin 1:8aa5cdb4ab67 46 * TODO: Meshing should also be considered - again a GLOSSY approach may be effective here, and highly complementary to
Jonathan Austin 1:8aa5cdb4ab67 47 * the master/slave arachitecture of BLE.
Jonathan Austin 1:8aa5cdb4ab67 48 *
Jonathan Austin 1:8aa5cdb4ab67 49 * TODO: This implementation may only operated whilst the BLE stack is disabled. The nrf51822 provides a timeslot API to allow
Jonathan Austin 1:8aa5cdb4ab67 50 * BLE to cohabit with other protocols. Future work to allow this colocation would be benefical, and would also allow for the
Jonathan Austin 1:8aa5cdb4ab67 51 * creation of wireless BLE bridges.
Jonathan Austin 1:8aa5cdb4ab67 52 *
Jonathan Austin 1:8aa5cdb4ab67 53 * NOTE: This API does not contain any form of encryption, authentication or authorisation. Its purpose is solely for use as a
Jonathan Austin 1:8aa5cdb4ab67 54 * teaching aid to demonstrate how simple communications operates, and to provide a sandpit through which learning can take place.
Jonathan Austin 1:8aa5cdb4ab67 55 * For serious applications, BLE should be considered a substantially more secure alternative.
Jonathan Austin 1:8aa5cdb4ab67 56 */
Jonathan Austin 1:8aa5cdb4ab67 57
Jonathan Austin 1:8aa5cdb4ab67 58 MicroBitRadio* MicroBitRadio::instance = NULL;
Jonathan Austin 1:8aa5cdb4ab67 59
Jonathan Austin 1:8aa5cdb4ab67 60 extern "C" void RADIO_IRQHandler(void)
Jonathan Austin 1:8aa5cdb4ab67 61 {
Jonathan Austin 1:8aa5cdb4ab67 62 // Move on to the next buffer, if possible.
Jonathan Austin 1:8aa5cdb4ab67 63 MicroBitRadio::instance->queueRxBuf();
Jonathan Austin 1:8aa5cdb4ab67 64 NRF_RADIO->PACKETPTR = (uint32_t) MicroBitRadio::instance->getRxBuf();
Jonathan Austin 1:8aa5cdb4ab67 65
Jonathan Austin 1:8aa5cdb4ab67 66 if(NRF_RADIO->EVENTS_READY)
Jonathan Austin 1:8aa5cdb4ab67 67 {
Jonathan Austin 1:8aa5cdb4ab67 68 NRF_RADIO->EVENTS_READY = 0;
Jonathan Austin 1:8aa5cdb4ab67 69
Jonathan Austin 1:8aa5cdb4ab67 70 // Start listening and wait for the END event
Jonathan Austin 1:8aa5cdb4ab67 71 NRF_RADIO->TASKS_START = 1;
Jonathan Austin 1:8aa5cdb4ab67 72 }
Jonathan Austin 1:8aa5cdb4ab67 73
Jonathan Austin 1:8aa5cdb4ab67 74 if(NRF_RADIO->EVENTS_END)
Jonathan Austin 1:8aa5cdb4ab67 75 {
Jonathan Austin 1:8aa5cdb4ab67 76 NRF_RADIO->EVENTS_END = 0;
Jonathan Austin 1:8aa5cdb4ab67 77
Jonathan Austin 1:8aa5cdb4ab67 78 if(NRF_RADIO->CRCSTATUS == 1)
Jonathan Austin 1:8aa5cdb4ab67 79 {
Jonathan Austin 1:8aa5cdb4ab67 80 uint8_t sample = NRF_RADIO->RSSISAMPLE;
Jonathan Austin 1:8aa5cdb4ab67 81
Jonathan Austin 1:8aa5cdb4ab67 82 MicroBitRadio::instance->setRSSI(sample);
Jonathan Austin 1:8aa5cdb4ab67 83 }
Jonathan Austin 1:8aa5cdb4ab67 84
Jonathan Austin 1:8aa5cdb4ab67 85 // Start listening and wait for the END event
Jonathan Austin 1:8aa5cdb4ab67 86 NRF_RADIO->TASKS_START = 1;
Jonathan Austin 1:8aa5cdb4ab67 87 }
Jonathan Austin 1:8aa5cdb4ab67 88 }
Jonathan Austin 1:8aa5cdb4ab67 89
Jonathan Austin 1:8aa5cdb4ab67 90 /**
Jonathan Austin 1:8aa5cdb4ab67 91 * Constructor.
Jonathan Austin 1:8aa5cdb4ab67 92 *
Jonathan Austin 1:8aa5cdb4ab67 93 * Initialise the MicroBitRadio.
Jonathan Austin 1:8aa5cdb4ab67 94 *
Jonathan Austin 1:8aa5cdb4ab67 95 * @note This class is demand activated, as a result most resources are only
Jonathan Austin 1:8aa5cdb4ab67 96 * committed if send/recv or event registrations calls are made.
Jonathan Austin 1:8aa5cdb4ab67 97 */
Jonathan Austin 1:8aa5cdb4ab67 98 MicroBitRadio::MicroBitRadio(uint16_t id) : datagram(*this), event (*this)
Jonathan Austin 1:8aa5cdb4ab67 99 {
Jonathan Austin 1:8aa5cdb4ab67 100 this->id = id;
Jonathan Austin 1:8aa5cdb4ab67 101 this->status = 0;
Jonathan Austin 1:8aa5cdb4ab67 102 this->group = 0;
Jonathan Austin 1:8aa5cdb4ab67 103 this->queueDepth = 0;
Jonathan Austin 1:8aa5cdb4ab67 104 this->rssi = 0;
Jonathan Austin 1:8aa5cdb4ab67 105 this->rxQueue = NULL;
Jonathan Austin 1:8aa5cdb4ab67 106 this->rxBuf = NULL;
Jonathan Austin 1:8aa5cdb4ab67 107
Jonathan Austin 1:8aa5cdb4ab67 108 instance = this;
Jonathan Austin 1:8aa5cdb4ab67 109 }
Jonathan Austin 1:8aa5cdb4ab67 110
Jonathan Austin 1:8aa5cdb4ab67 111 /**
Jonathan Austin 1:8aa5cdb4ab67 112 * Change the output power level of the transmitter to the given value.
Jonathan Austin 1:8aa5cdb4ab67 113 *
Jonathan Austin 1:8aa5cdb4ab67 114 * @param power a value in the range 0..7, where 0 is the lowest power and 7 is the highest.
Jonathan Austin 1:8aa5cdb4ab67 115 *
Jonathan Austin 1:8aa5cdb4ab67 116 * @return MICROBIT_OK on success, or MICROBIT_INVALID_PARAMETER if the value is out of range.
Jonathan Austin 1:8aa5cdb4ab67 117 */
Jonathan Austin 1:8aa5cdb4ab67 118 int MicroBitRadio::setTransmitPower(int power)
Jonathan Austin 1:8aa5cdb4ab67 119 {
Jonathan Austin 1:8aa5cdb4ab67 120 if (power < 0 || power >= MICROBIT_BLE_POWER_LEVELS)
Jonathan Austin 1:8aa5cdb4ab67 121 return MICROBIT_INVALID_PARAMETER;
Jonathan Austin 1:8aa5cdb4ab67 122
Jonathan Austin 1:8aa5cdb4ab67 123 NRF_RADIO->TXPOWER = (uint32_t)MICROBIT_BLE_POWER_LEVEL[power];
Jonathan Austin 1:8aa5cdb4ab67 124
Jonathan Austin 1:8aa5cdb4ab67 125 return MICROBIT_OK;
Jonathan Austin 1:8aa5cdb4ab67 126 }
Jonathan Austin 1:8aa5cdb4ab67 127
Jonathan Austin 1:8aa5cdb4ab67 128 /**
Jonathan Austin 1:8aa5cdb4ab67 129 * Change the transmission and reception band of the radio to the given channel
Jonathan Austin 1:8aa5cdb4ab67 130 *
Jonathan Austin 1:8aa5cdb4ab67 131 * @param band a frequency band in the range 0 - 100. Each step is 1MHz wide, based at 2400MHz.
Jonathan Austin 1:8aa5cdb4ab67 132 *
Jonathan Austin 1:8aa5cdb4ab67 133 * @return MICROBIT_OK on success, or MICROBIT_INVALID_PARAMETER if the value is out of range,
Jonathan Austin 1:8aa5cdb4ab67 134 * or MICROBIT_NOT_SUPPORTED if the BLE stack is running.
Jonathan Austin 1:8aa5cdb4ab67 135 */
Jonathan Austin 1:8aa5cdb4ab67 136 int MicroBitRadio::setFrequencyBand(int band)
Jonathan Austin 1:8aa5cdb4ab67 137 {
Jonathan Austin 1:8aa5cdb4ab67 138 if (ble_running())
Jonathan Austin 1:8aa5cdb4ab67 139 return MICROBIT_NOT_SUPPORTED;
Jonathan Austin 1:8aa5cdb4ab67 140
Jonathan Austin 1:8aa5cdb4ab67 141 if (band < 0 || band > 100)
Jonathan Austin 1:8aa5cdb4ab67 142 return MICROBIT_INVALID_PARAMETER;
Jonathan Austin 1:8aa5cdb4ab67 143
Jonathan Austin 1:8aa5cdb4ab67 144 NRF_RADIO->FREQUENCY = (uint32_t)band;
Jonathan Austin 1:8aa5cdb4ab67 145
Jonathan Austin 1:8aa5cdb4ab67 146 return MICROBIT_OK;
Jonathan Austin 1:8aa5cdb4ab67 147 }
Jonathan Austin 1:8aa5cdb4ab67 148
Jonathan Austin 1:8aa5cdb4ab67 149 /**
Jonathan Austin 1:8aa5cdb4ab67 150 * Retrieve a pointer to the currently allocated receive buffer. This is the area of memory
Jonathan Austin 1:8aa5cdb4ab67 151 * actively being used by the radio hardware to store incoming data.
Jonathan Austin 1:8aa5cdb4ab67 152 *
Jonathan Austin 1:8aa5cdb4ab67 153 * @return a pointer to the current receive buffer.
Jonathan Austin 1:8aa5cdb4ab67 154 */
Jonathan Austin 1:8aa5cdb4ab67 155 FrameBuffer* MicroBitRadio::getRxBuf()
Jonathan Austin 1:8aa5cdb4ab67 156 {
Jonathan Austin 1:8aa5cdb4ab67 157 return rxBuf;
Jonathan Austin 1:8aa5cdb4ab67 158 }
Jonathan Austin 1:8aa5cdb4ab67 159
Jonathan Austin 1:8aa5cdb4ab67 160 /**
Jonathan Austin 1:8aa5cdb4ab67 161 * Attempt to queue a buffer received by the radio hardware, if sufficient space is available.
Jonathan Austin 1:8aa5cdb4ab67 162 *
Jonathan Austin 1:8aa5cdb4ab67 163 * @return MICROBIT_OK on success, or MICROBIT_NO_RESOURCES if a replacement receiver buffer
Jonathan Austin 1:8aa5cdb4ab67 164 * could not be allocated (either by policy or memory exhaustion).
Jonathan Austin 1:8aa5cdb4ab67 165 */
Jonathan Austin 1:8aa5cdb4ab67 166 int MicroBitRadio::queueRxBuf()
Jonathan Austin 1:8aa5cdb4ab67 167 {
Jonathan Austin 1:8aa5cdb4ab67 168 if (rxBuf == NULL)
Jonathan Austin 1:8aa5cdb4ab67 169 return MICROBIT_INVALID_PARAMETER;
Jonathan Austin 1:8aa5cdb4ab67 170
Jonathan Austin 1:8aa5cdb4ab67 171 if (queueDepth >= MICROBIT_RADIO_MAXIMUM_RX_BUFFERS)
Jonathan Austin 1:8aa5cdb4ab67 172 return MICROBIT_NO_RESOURCES;
Jonathan Austin 1:8aa5cdb4ab67 173
Jonathan Austin 1:8aa5cdb4ab67 174 // Store the received RSSI value in the frame
Jonathan Austin 1:8aa5cdb4ab67 175 rxBuf->rssi = getRSSI();
Jonathan Austin 1:8aa5cdb4ab67 176
Jonathan Austin 1:8aa5cdb4ab67 177 // Ensure that a replacement buffer is available before queuing.
Jonathan Austin 1:8aa5cdb4ab67 178 FrameBuffer *newRxBuf = new FrameBuffer();
Jonathan Austin 1:8aa5cdb4ab67 179
Jonathan Austin 1:8aa5cdb4ab67 180 if (newRxBuf == NULL)
Jonathan Austin 1:8aa5cdb4ab67 181 return MICROBIT_NO_RESOURCES;
Jonathan Austin 1:8aa5cdb4ab67 182
Jonathan Austin 1:8aa5cdb4ab67 183 // We add to the tail of the queue to preserve causal ordering.
Jonathan Austin 1:8aa5cdb4ab67 184 rxBuf->next = NULL;
Jonathan Austin 1:8aa5cdb4ab67 185
Jonathan Austin 1:8aa5cdb4ab67 186 if (rxQueue == NULL)
Jonathan Austin 1:8aa5cdb4ab67 187 {
Jonathan Austin 1:8aa5cdb4ab67 188 rxQueue = rxBuf;
Jonathan Austin 1:8aa5cdb4ab67 189 }
Jonathan Austin 1:8aa5cdb4ab67 190 else
Jonathan Austin 1:8aa5cdb4ab67 191 {
Jonathan Austin 1:8aa5cdb4ab67 192 FrameBuffer *p = rxQueue;
Jonathan Austin 1:8aa5cdb4ab67 193 while (p->next != NULL)
Jonathan Austin 1:8aa5cdb4ab67 194 p = p->next;
Jonathan Austin 1:8aa5cdb4ab67 195
Jonathan Austin 1:8aa5cdb4ab67 196 p->next = rxBuf;
Jonathan Austin 1:8aa5cdb4ab67 197 }
Jonathan Austin 1:8aa5cdb4ab67 198
Jonathan Austin 1:8aa5cdb4ab67 199 // Increase our received packet count
Jonathan Austin 1:8aa5cdb4ab67 200 queueDepth++;
Jonathan Austin 1:8aa5cdb4ab67 201
Jonathan Austin 1:8aa5cdb4ab67 202 // Allocate a new buffer for the receiver hardware to use. the old on will be passed on to higher layer protocols/apps.
Jonathan Austin 1:8aa5cdb4ab67 203 rxBuf = newRxBuf;
Jonathan Austin 1:8aa5cdb4ab67 204
Jonathan Austin 1:8aa5cdb4ab67 205 return MICROBIT_OK;
Jonathan Austin 1:8aa5cdb4ab67 206 }
Jonathan Austin 1:8aa5cdb4ab67 207
Jonathan Austin 1:8aa5cdb4ab67 208 /**
Jonathan Austin 1:8aa5cdb4ab67 209 * Sets the RSSI for the most recent packet.
Jonathan Austin 1:8aa5cdb4ab67 210 *
Jonathan Austin 1:8aa5cdb4ab67 211 * @param rssi the new rssi value.
Jonathan Austin 1:8aa5cdb4ab67 212 *
Jonathan Austin 1:8aa5cdb4ab67 213 * @note should only be called from RADIO_IRQHandler...
Jonathan Austin 1:8aa5cdb4ab67 214 */
Jonathan Austin 1:8aa5cdb4ab67 215 int MicroBitRadio::setRSSI(uint8_t rssi)
Jonathan Austin 1:8aa5cdb4ab67 216 {
Jonathan Austin 1:8aa5cdb4ab67 217 if (!(status & MICROBIT_RADIO_STATUS_INITIALISED))
Jonathan Austin 1:8aa5cdb4ab67 218 return MICROBIT_NOT_SUPPORTED;
Jonathan Austin 1:8aa5cdb4ab67 219
Jonathan Austin 1:8aa5cdb4ab67 220 this->rssi = rssi;
Jonathan Austin 1:8aa5cdb4ab67 221
Jonathan Austin 1:8aa5cdb4ab67 222 return MICROBIT_OK;
Jonathan Austin 1:8aa5cdb4ab67 223 }
Jonathan Austin 1:8aa5cdb4ab67 224
Jonathan Austin 1:8aa5cdb4ab67 225 /**
Jonathan Austin 1:8aa5cdb4ab67 226 * Retrieves the current RSSI for the most recent packet.
Jonathan Austin 1:8aa5cdb4ab67 227 *
Jonathan Austin 1:8aa5cdb4ab67 228 * @return the most recent RSSI value or MICROBIT_NOT_SUPPORTED if the BLE stack is running.
Jonathan Austin 1:8aa5cdb4ab67 229 */
Jonathan Austin 1:8aa5cdb4ab67 230 int MicroBitRadio::getRSSI()
Jonathan Austin 1:8aa5cdb4ab67 231 {
Jonathan Austin 1:8aa5cdb4ab67 232 if (!(status & MICROBIT_RADIO_STATUS_INITIALISED))
Jonathan Austin 1:8aa5cdb4ab67 233 return MICROBIT_NOT_SUPPORTED;
Jonathan Austin 1:8aa5cdb4ab67 234
Jonathan Austin 1:8aa5cdb4ab67 235 return this->rssi;
Jonathan Austin 1:8aa5cdb4ab67 236 }
Jonathan Austin 1:8aa5cdb4ab67 237
Jonathan Austin 1:8aa5cdb4ab67 238 /**
Jonathan Austin 1:8aa5cdb4ab67 239 * Initialises the radio for use as a multipoint sender/receiver
Jonathan Austin 1:8aa5cdb4ab67 240 *
Jonathan Austin 1:8aa5cdb4ab67 241 * @return MICROBIT_OK on success, MICROBIT_NOT_SUPPORTED if the BLE stack is running.
Jonathan Austin 1:8aa5cdb4ab67 242 */
Jonathan Austin 1:8aa5cdb4ab67 243 int MicroBitRadio::enable()
Jonathan Austin 1:8aa5cdb4ab67 244 {
Jonathan Austin 1:8aa5cdb4ab67 245 // If the device is already initialised, then there's nothing to do.
Jonathan Austin 1:8aa5cdb4ab67 246 if (status & MICROBIT_RADIO_STATUS_INITIALISED)
Jonathan Austin 1:8aa5cdb4ab67 247 return MICROBIT_OK;
Jonathan Austin 1:8aa5cdb4ab67 248
Jonathan Austin 1:8aa5cdb4ab67 249 // Only attempt to enable this radio mode if BLE is disabled.
Jonathan Austin 1:8aa5cdb4ab67 250 if (ble_running())
Jonathan Austin 1:8aa5cdb4ab67 251 return MICROBIT_NOT_SUPPORTED;
Jonathan Austin 1:8aa5cdb4ab67 252
Jonathan Austin 1:8aa5cdb4ab67 253 // If this is the first time we've been enable, allocate out receive buffers.
Jonathan Austin 1:8aa5cdb4ab67 254 if (rxBuf == NULL)
Jonathan Austin 1:8aa5cdb4ab67 255 rxBuf = new FrameBuffer();
Jonathan Austin 1:8aa5cdb4ab67 256
Jonathan Austin 1:8aa5cdb4ab67 257 if (rxBuf == NULL)
Jonathan Austin 1:8aa5cdb4ab67 258 return MICROBIT_NO_RESOURCES;
Jonathan Austin 1:8aa5cdb4ab67 259
Jonathan Austin 1:8aa5cdb4ab67 260 // Enable the High Frequency clock on the processor. This is a pre-requisite for
Jonathan Austin 1:8aa5cdb4ab67 261 // the RADIO module. Without this clock, no communication is possible.
Jonathan Austin 1:8aa5cdb4ab67 262 NRF_CLOCK->EVENTS_HFCLKSTARTED = 0;
Jonathan Austin 1:8aa5cdb4ab67 263 NRF_CLOCK->TASKS_HFCLKSTART = 1;
Jonathan Austin 1:8aa5cdb4ab67 264 while (NRF_CLOCK->EVENTS_HFCLKSTARTED == 0);
Jonathan Austin 1:8aa5cdb4ab67 265
Jonathan Austin 1:8aa5cdb4ab67 266 // Bring up the nrf51822 RADIO module in Nordic's proprietary 1MBps packet radio mode.
Jonathan Austin 1:8aa5cdb4ab67 267 setTransmitPower(MICROBIT_RADIO_DEFAULT_TX_POWER);
Jonathan Austin 1:8aa5cdb4ab67 268 setFrequencyBand(MICROBIT_RADIO_DEFAULT_FREQUENCY);
Jonathan Austin 1:8aa5cdb4ab67 269
Jonathan Austin 1:8aa5cdb4ab67 270 // Configure for 1Mbps throughput.
Jonathan Austin 1:8aa5cdb4ab67 271 // This may sound excessive, but running a high data rates reduces the chances of collisions...
Jonathan Austin 1:8aa5cdb4ab67 272 NRF_RADIO->MODE = RADIO_MODE_MODE_Nrf_1Mbit;
Jonathan Austin 1:8aa5cdb4ab67 273
Jonathan Austin 1:8aa5cdb4ab67 274 // Configure the addresses we use for this protocol. We run ANONYMOUSLY at the core.
Jonathan Austin 1:8aa5cdb4ab67 275 // A 40 bit addresses is used. The first 32 bits match the ASCII character code for "uBit".
Jonathan Austin 1:8aa5cdb4ab67 276 // Statistically, this provides assurance to avoid other similar 2.4GHz protocols that may be in the vicinity.
Jonathan Austin 1:8aa5cdb4ab67 277 // We also map the assigned 8-bit GROUP id into the PREFIX field. This allows the RADIO hardware to perform
Jonathan Austin 1:8aa5cdb4ab67 278 // address matching for us, and only generate an interrupt when a packet matching our group is received.
Jonathan Austin 1:8aa5cdb4ab67 279 NRF_RADIO->BASE0 = MICROBIT_RADIO_BASE_ADDRESS;
Jonathan Austin 1:8aa5cdb4ab67 280
Jonathan Austin 1:8aa5cdb4ab67 281 // Join the default group. This will configure the remaining byte in the RADIO hardware module.
Jonathan Austin 1:8aa5cdb4ab67 282 setGroup(MICROBIT_RADIO_DEFAULT_GROUP);
Jonathan Austin 1:8aa5cdb4ab67 283
Jonathan Austin 1:8aa5cdb4ab67 284 // The RADIO hardware module supports the use of multiple addresses, but as we're running anonymously, we only need one.
Jonathan Austin 1:8aa5cdb4ab67 285 // Configure the RADIO module to use the default address (address 0) for both send and receive operations.
Jonathan Austin 1:8aa5cdb4ab67 286 NRF_RADIO->TXADDRESS = 0;
Jonathan Austin 1:8aa5cdb4ab67 287 NRF_RADIO->RXADDRESSES = 1;
Jonathan Austin 1:8aa5cdb4ab67 288
Jonathan Austin 1:8aa5cdb4ab67 289 // Packet layout configuration. The nrf51822 has a highly capable and flexible RADIO module that, in addition to transmission
Jonathan Austin 1:8aa5cdb4ab67 290 // and reception of data, also contains a LENGTH field, two optional additional 1 byte fields (S0 and S1) and a CRC calculation.
Jonathan Austin 1:8aa5cdb4ab67 291 // Configure the packet format for a simple 8 bit length field and no additional fields.
Jonathan Austin 1:8aa5cdb4ab67 292 NRF_RADIO->PCNF0 = 0x00000008;
Jonathan Austin 1:8aa5cdb4ab67 293 NRF_RADIO->PCNF1 = 0x02040000 | MICROBIT_RADIO_MAX_PACKET_SIZE;
Jonathan Austin 1:8aa5cdb4ab67 294
Jonathan Austin 1:8aa5cdb4ab67 295 // Most communication channels contain some form of checksum - a mathematical calculation taken based on all the data
Jonathan Austin 1:8aa5cdb4ab67 296 // in a packet, that is also sent as part of the packet. When received, this calculation can be repeated, and the results
Jonathan Austin 1:8aa5cdb4ab67 297 // from the sender and receiver compared. If they are different, then some corruption of the data ahas happened in transit,
Jonathan Austin 1:8aa5cdb4ab67 298 // and we know we can't trust it. The nrf51822 RADIO uses a CRC for this - a very effective checksum calculation.
Jonathan Austin 1:8aa5cdb4ab67 299 //
Jonathan Austin 1:8aa5cdb4ab67 300 // Enable automatic 16bit CRC generation and checking, and configure how the CRC is calculated.
Jonathan Austin 1:8aa5cdb4ab67 301 NRF_RADIO->CRCCNF = RADIO_CRCCNF_LEN_Two;
Jonathan Austin 1:8aa5cdb4ab67 302 NRF_RADIO->CRCINIT = 0xFFFF;
Jonathan Austin 1:8aa5cdb4ab67 303 NRF_RADIO->CRCPOLY = 0x11021;
Jonathan Austin 1:8aa5cdb4ab67 304
Jonathan Austin 1:8aa5cdb4ab67 305 // Set the start random value of the data whitening algorithm. This can be any non zero number.
Jonathan Austin 1:8aa5cdb4ab67 306 NRF_RADIO->DATAWHITEIV = 0x18;
Jonathan Austin 1:8aa5cdb4ab67 307
Jonathan Austin 1:8aa5cdb4ab67 308 // Set up the RADIO module to read and write from our internal buffer.
Jonathan Austin 1:8aa5cdb4ab67 309 NRF_RADIO->PACKETPTR = (uint32_t)rxBuf;
Jonathan Austin 1:8aa5cdb4ab67 310
Jonathan Austin 1:8aa5cdb4ab67 311 // Configure the hardware to issue an interrupt whenever a task is complete (e.g. send/receive).
Jonathan Austin 1:8aa5cdb4ab67 312 NRF_RADIO->INTENSET = 0x00000008;
Jonathan Austin 1:8aa5cdb4ab67 313 NVIC_ClearPendingIRQ(RADIO_IRQn);
Jonathan Austin 1:8aa5cdb4ab67 314 NVIC_EnableIRQ(RADIO_IRQn);
Jonathan Austin 1:8aa5cdb4ab67 315
Jonathan Austin 1:8aa5cdb4ab67 316 NRF_RADIO->SHORTS |= RADIO_SHORTS_ADDRESS_RSSISTART_Msk;
Jonathan Austin 1:8aa5cdb4ab67 317
Jonathan Austin 1:8aa5cdb4ab67 318 // Start listening for the next packet
Jonathan Austin 1:8aa5cdb4ab67 319 NRF_RADIO->EVENTS_READY = 0;
Jonathan Austin 1:8aa5cdb4ab67 320 NRF_RADIO->TASKS_RXEN = 1;
Jonathan Austin 1:8aa5cdb4ab67 321 while(NRF_RADIO->EVENTS_READY == 0);
Jonathan Austin 1:8aa5cdb4ab67 322
Jonathan Austin 1:8aa5cdb4ab67 323 NRF_RADIO->EVENTS_END = 0;
Jonathan Austin 1:8aa5cdb4ab67 324 NRF_RADIO->TASKS_START = 1;
Jonathan Austin 1:8aa5cdb4ab67 325
Jonathan Austin 1:8aa5cdb4ab67 326 // register ourselves for a callback event, in order to empty the receive queue.
Jonathan Austin 1:8aa5cdb4ab67 327 fiber_add_idle_component(this);
Jonathan Austin 1:8aa5cdb4ab67 328
Jonathan Austin 1:8aa5cdb4ab67 329 // Done. Record that our RADIO is configured.
Jonathan Austin 1:8aa5cdb4ab67 330 status |= MICROBIT_RADIO_STATUS_INITIALISED;
Jonathan Austin 1:8aa5cdb4ab67 331
Jonathan Austin 1:8aa5cdb4ab67 332 return MICROBIT_OK;
Jonathan Austin 1:8aa5cdb4ab67 333 }
Jonathan Austin 1:8aa5cdb4ab67 334
Jonathan Austin 1:8aa5cdb4ab67 335 /**
Jonathan Austin 1:8aa5cdb4ab67 336 * Disables the radio for use as a multipoint sender/receiver.
Jonathan Austin 1:8aa5cdb4ab67 337 *
Jonathan Austin 1:8aa5cdb4ab67 338 * @return MICROBIT_OK on success, MICROBIT_NOT_SUPPORTED if the BLE stack is running.
Jonathan Austin 1:8aa5cdb4ab67 339 */
Jonathan Austin 1:8aa5cdb4ab67 340 int MicroBitRadio::disable()
Jonathan Austin 1:8aa5cdb4ab67 341 {
Jonathan Austin 1:8aa5cdb4ab67 342 // Only attempt to enable.disable the radio if the protocol is alreayd running.
Jonathan Austin 1:8aa5cdb4ab67 343 if (ble_running())
Jonathan Austin 1:8aa5cdb4ab67 344 return MICROBIT_NOT_SUPPORTED;
Jonathan Austin 1:8aa5cdb4ab67 345
Jonathan Austin 1:8aa5cdb4ab67 346 if (!(status & MICROBIT_RADIO_STATUS_INITIALISED))
Jonathan Austin 1:8aa5cdb4ab67 347 return MICROBIT_OK;
Jonathan Austin 1:8aa5cdb4ab67 348
Jonathan Austin 1:8aa5cdb4ab67 349 // Disable interrupts and STOP any ongoing packet reception.
Jonathan Austin 1:8aa5cdb4ab67 350 NVIC_DisableIRQ(RADIO_IRQn);
Jonathan Austin 1:8aa5cdb4ab67 351
Jonathan Austin 1:8aa5cdb4ab67 352 NRF_RADIO->EVENTS_DISABLED = 0;
Jonathan Austin 1:8aa5cdb4ab67 353 NRF_RADIO->TASKS_DISABLE = 1;
Jonathan Austin 1:8aa5cdb4ab67 354 while(NRF_RADIO->EVENTS_DISABLED == 0);
Jonathan Austin 1:8aa5cdb4ab67 355
Jonathan Austin 1:8aa5cdb4ab67 356 // deregister ourselves from the callback event used to empty the receive queue.
Jonathan Austin 1:8aa5cdb4ab67 357 fiber_remove_idle_component(this);
Jonathan Austin 1:8aa5cdb4ab67 358
LancasterUniversity 18:e2f92ac26450 359 // record that the radio is now disabled
LancasterUniversity 18:e2f92ac26450 360 status &= ~MICROBIT_RADIO_STATUS_INITIALISED;
LancasterUniversity 18:e2f92ac26450 361
Jonathan Austin 1:8aa5cdb4ab67 362 return MICROBIT_OK;
Jonathan Austin 1:8aa5cdb4ab67 363 }
Jonathan Austin 1:8aa5cdb4ab67 364
Jonathan Austin 1:8aa5cdb4ab67 365 /**
Jonathan Austin 1:8aa5cdb4ab67 366 * Sets the radio to listen to packets sent with the given group id.
Jonathan Austin 1:8aa5cdb4ab67 367 *
Jonathan Austin 1:8aa5cdb4ab67 368 * @param group The group to join. A micro:bit can only listen to one group ID at any time.
Jonathan Austin 1:8aa5cdb4ab67 369 *
Jonathan Austin 1:8aa5cdb4ab67 370 * @return MICROBIT_OK on success, or MICROBIT_NOT_SUPPORTED if the BLE stack is running.
Jonathan Austin 1:8aa5cdb4ab67 371 */
Jonathan Austin 1:8aa5cdb4ab67 372 int MicroBitRadio::setGroup(uint8_t group)
Jonathan Austin 1:8aa5cdb4ab67 373 {
Jonathan Austin 1:8aa5cdb4ab67 374 if (ble_running())
Jonathan Austin 1:8aa5cdb4ab67 375 return MICROBIT_NOT_SUPPORTED;
Jonathan Austin 1:8aa5cdb4ab67 376
Jonathan Austin 1:8aa5cdb4ab67 377 // Record our group id locally
Jonathan Austin 1:8aa5cdb4ab67 378 this->group = group;
Jonathan Austin 1:8aa5cdb4ab67 379
Jonathan Austin 1:8aa5cdb4ab67 380 // Also append it to the address of this device, to allow the RADIO module to filter for us.
Jonathan Austin 1:8aa5cdb4ab67 381 NRF_RADIO->PREFIX0 = (uint32_t)group;
Jonathan Austin 1:8aa5cdb4ab67 382
Jonathan Austin 1:8aa5cdb4ab67 383 return MICROBIT_OK;
Jonathan Austin 1:8aa5cdb4ab67 384 }
Jonathan Austin 1:8aa5cdb4ab67 385
Jonathan Austin 1:8aa5cdb4ab67 386 /**
Jonathan Austin 1:8aa5cdb4ab67 387 * A background, low priority callback that is triggered whenever the processor is idle.
Jonathan Austin 1:8aa5cdb4ab67 388 * Here, we empty our queue of received packets, and pass them onto higher level protocol handlers.
Jonathan Austin 1:8aa5cdb4ab67 389 */
Jonathan Austin 1:8aa5cdb4ab67 390 void MicroBitRadio::idleTick()
Jonathan Austin 1:8aa5cdb4ab67 391 {
Jonathan Austin 1:8aa5cdb4ab67 392 // Walk the list of packets and process each one.
Jonathan Austin 1:8aa5cdb4ab67 393 while(rxQueue)
Jonathan Austin 1:8aa5cdb4ab67 394 {
Jonathan Austin 1:8aa5cdb4ab67 395 FrameBuffer *p = rxQueue;
Jonathan Austin 1:8aa5cdb4ab67 396
Jonathan Austin 1:8aa5cdb4ab67 397 switch (p->protocol)
Jonathan Austin 1:8aa5cdb4ab67 398 {
Jonathan Austin 1:8aa5cdb4ab67 399 case MICROBIT_RADIO_PROTOCOL_DATAGRAM:
Jonathan Austin 1:8aa5cdb4ab67 400 datagram.packetReceived();
Jonathan Austin 1:8aa5cdb4ab67 401 break;
Jonathan Austin 1:8aa5cdb4ab67 402
Jonathan Austin 1:8aa5cdb4ab67 403 case MICROBIT_RADIO_PROTOCOL_EVENTBUS:
Jonathan Austin 1:8aa5cdb4ab67 404 event.packetReceived();
Jonathan Austin 1:8aa5cdb4ab67 405 break;
Jonathan Austin 1:8aa5cdb4ab67 406
Jonathan Austin 1:8aa5cdb4ab67 407 default:
Jonathan Austin 1:8aa5cdb4ab67 408 MicroBitEvent(MICROBIT_ID_RADIO_DATA_READY, p->protocol);
Jonathan Austin 1:8aa5cdb4ab67 409 }
Jonathan Austin 1:8aa5cdb4ab67 410
Jonathan Austin 1:8aa5cdb4ab67 411 // If the packet was processed, it will have been recv'd, and taken from the queue.
Jonathan Austin 1:8aa5cdb4ab67 412 // If this was a packet for an unknown protocol, it will still be there, so simply free it.
Jonathan Austin 1:8aa5cdb4ab67 413 if (p == rxQueue)
Jonathan Austin 1:8aa5cdb4ab67 414 {
Jonathan Austin 1:8aa5cdb4ab67 415 recv();
Jonathan Austin 1:8aa5cdb4ab67 416 delete p;
Jonathan Austin 1:8aa5cdb4ab67 417 }
Jonathan Austin 1:8aa5cdb4ab67 418 }
Jonathan Austin 1:8aa5cdb4ab67 419 }
Jonathan Austin 1:8aa5cdb4ab67 420
Jonathan Austin 1:8aa5cdb4ab67 421 /**
Jonathan Austin 1:8aa5cdb4ab67 422 * Determines the number of packets ready to be processed.
Jonathan Austin 1:8aa5cdb4ab67 423 *
Jonathan Austin 1:8aa5cdb4ab67 424 * @return The number of packets in the receive buffer.
Jonathan Austin 1:8aa5cdb4ab67 425 */
Jonathan Austin 1:8aa5cdb4ab67 426 int MicroBitRadio::dataReady()
Jonathan Austin 1:8aa5cdb4ab67 427 {
Jonathan Austin 1:8aa5cdb4ab67 428 return queueDepth;
Jonathan Austin 1:8aa5cdb4ab67 429 }
Jonathan Austin 1:8aa5cdb4ab67 430
Jonathan Austin 1:8aa5cdb4ab67 431 /**
Jonathan Austin 1:8aa5cdb4ab67 432 * Retrieves the next packet from the receive buffer.
Jonathan Austin 1:8aa5cdb4ab67 433 * If a data packet is available, then it will be returned immediately to
Jonathan Austin 1:8aa5cdb4ab67 434 * the caller. This call will also dequeue the buffer.
Jonathan Austin 1:8aa5cdb4ab67 435 *
Jonathan Austin 1:8aa5cdb4ab67 436 * @return The buffer containing the the packet. If no data is available, NULL is returned.
Jonathan Austin 1:8aa5cdb4ab67 437 *
Jonathan Austin 1:8aa5cdb4ab67 438 * @note Once recv() has been called, it is the callers resposibility to
Jonathan Austin 1:8aa5cdb4ab67 439 * delete the buffer when appropriate.
Jonathan Austin 1:8aa5cdb4ab67 440 */
Jonathan Austin 1:8aa5cdb4ab67 441 FrameBuffer* MicroBitRadio::recv()
Jonathan Austin 1:8aa5cdb4ab67 442 {
Jonathan Austin 1:8aa5cdb4ab67 443 FrameBuffer *p = rxQueue;
Jonathan Austin 1:8aa5cdb4ab67 444
Jonathan Austin 1:8aa5cdb4ab67 445 if (p)
Jonathan Austin 1:8aa5cdb4ab67 446 {
Jonathan Austin 1:8aa5cdb4ab67 447 rxQueue = rxQueue->next;
Jonathan Austin 1:8aa5cdb4ab67 448 queueDepth--;
Jonathan Austin 1:8aa5cdb4ab67 449 }
Jonathan Austin 1:8aa5cdb4ab67 450
Jonathan Austin 1:8aa5cdb4ab67 451 return p;
Jonathan Austin 1:8aa5cdb4ab67 452 }
Jonathan Austin 1:8aa5cdb4ab67 453
Jonathan Austin 1:8aa5cdb4ab67 454 /**
Jonathan Austin 1:8aa5cdb4ab67 455 * Transmits the given buffer onto the broadcast radio.
Jonathan Austin 1:8aa5cdb4ab67 456 * The call will wait until the transmission of the packet has completed before returning.
Jonathan Austin 1:8aa5cdb4ab67 457 *
Jonathan Austin 1:8aa5cdb4ab67 458 * @param data The packet contents to transmit.
Jonathan Austin 1:8aa5cdb4ab67 459 *
Jonathan Austin 1:8aa5cdb4ab67 460 * @return MICROBIT_OK on success, or MICROBIT_NOT_SUPPORTED if the BLE stack is running.
Jonathan Austin 1:8aa5cdb4ab67 461 */
Jonathan Austin 1:8aa5cdb4ab67 462 int MicroBitRadio::send(FrameBuffer *buffer)
Jonathan Austin 1:8aa5cdb4ab67 463 {
Jonathan Austin 1:8aa5cdb4ab67 464 if (ble_running())
Jonathan Austin 1:8aa5cdb4ab67 465 return MICROBIT_NOT_SUPPORTED;
Jonathan Austin 1:8aa5cdb4ab67 466
Jonathan Austin 1:8aa5cdb4ab67 467 if (buffer == NULL)
Jonathan Austin 1:8aa5cdb4ab67 468 return MICROBIT_INVALID_PARAMETER;
Jonathan Austin 1:8aa5cdb4ab67 469
Jonathan Austin 1:8aa5cdb4ab67 470 if (buffer->length > MICROBIT_RADIO_MAX_PACKET_SIZE + MICROBIT_RADIO_HEADER_SIZE - 1)
Jonathan Austin 1:8aa5cdb4ab67 471 return MICROBIT_INVALID_PARAMETER;
Jonathan Austin 1:8aa5cdb4ab67 472
Jonathan Austin 1:8aa5cdb4ab67 473 // Firstly, disable the Radio interrupt. We want to wait until the trasmission completes.
Jonathan Austin 1:8aa5cdb4ab67 474 NVIC_DisableIRQ(RADIO_IRQn);
Jonathan Austin 1:8aa5cdb4ab67 475
Jonathan Austin 1:8aa5cdb4ab67 476 // Turn off the transceiver.
Jonathan Austin 1:8aa5cdb4ab67 477 NRF_RADIO->EVENTS_DISABLED = 0;
Jonathan Austin 1:8aa5cdb4ab67 478 NRF_RADIO->TASKS_DISABLE = 1;
Jonathan Austin 1:8aa5cdb4ab67 479 while(NRF_RADIO->EVENTS_DISABLED == 0);
Jonathan Austin 1:8aa5cdb4ab67 480
Jonathan Austin 1:8aa5cdb4ab67 481 // Configure the radio to send the buffer provided.
Jonathan Austin 1:8aa5cdb4ab67 482 NRF_RADIO->PACKETPTR = (uint32_t) buffer;
Jonathan Austin 1:8aa5cdb4ab67 483
Jonathan Austin 1:8aa5cdb4ab67 484 // Turn on the transmitter, and wait for it to signal that it's ready to use.
Jonathan Austin 1:8aa5cdb4ab67 485 NRF_RADIO->EVENTS_READY = 0;
Jonathan Austin 1:8aa5cdb4ab67 486 NRF_RADIO->TASKS_TXEN = 1;
Jonathan Austin 1:8aa5cdb4ab67 487 while (NRF_RADIO->EVENTS_READY == 0);
Jonathan Austin 1:8aa5cdb4ab67 488
Jonathan Austin 1:8aa5cdb4ab67 489 // Start transmission and wait for end of packet.
Jonathan Austin 1:8aa5cdb4ab67 490 NRF_RADIO->TASKS_START = 1;
Jonathan Austin 1:8aa5cdb4ab67 491 NRF_RADIO->EVENTS_END = 0;
Jonathan Austin 1:8aa5cdb4ab67 492 while(NRF_RADIO->EVENTS_END == 0);
Jonathan Austin 1:8aa5cdb4ab67 493
Jonathan Austin 1:8aa5cdb4ab67 494 // Return the radio to using the default receive buffer
Jonathan Austin 1:8aa5cdb4ab67 495 NRF_RADIO->PACKETPTR = (uint32_t) rxBuf;
Jonathan Austin 1:8aa5cdb4ab67 496
Jonathan Austin 1:8aa5cdb4ab67 497 // Turn off the transmitter.
Jonathan Austin 1:8aa5cdb4ab67 498 NRF_RADIO->EVENTS_DISABLED = 0;
Jonathan Austin 1:8aa5cdb4ab67 499 NRF_RADIO->TASKS_DISABLE = 1;
Jonathan Austin 1:8aa5cdb4ab67 500 while(NRF_RADIO->EVENTS_DISABLED == 0);
Jonathan Austin 1:8aa5cdb4ab67 501
Jonathan Austin 1:8aa5cdb4ab67 502 // Start listening for the next packet
Jonathan Austin 1:8aa5cdb4ab67 503 NRF_RADIO->EVENTS_READY = 0;
Jonathan Austin 1:8aa5cdb4ab67 504 NRF_RADIO->TASKS_RXEN = 1;
Jonathan Austin 1:8aa5cdb4ab67 505 while(NRF_RADIO->EVENTS_READY == 0);
Jonathan Austin 1:8aa5cdb4ab67 506
Jonathan Austin 1:8aa5cdb4ab67 507 NRF_RADIO->EVENTS_END = 0;
Jonathan Austin 1:8aa5cdb4ab67 508 NRF_RADIO->TASKS_START = 1;
Jonathan Austin 1:8aa5cdb4ab67 509
Jonathan Austin 1:8aa5cdb4ab67 510 // Re-enable the Radio interrupt.
Jonathan Austin 1:8aa5cdb4ab67 511 NVIC_ClearPendingIRQ(RADIO_IRQn);
Jonathan Austin 1:8aa5cdb4ab67 512 NVIC_EnableIRQ(RADIO_IRQn);
Jonathan Austin 1:8aa5cdb4ab67 513
Jonathan Austin 1:8aa5cdb4ab67 514 return MICROBIT_OK;
LancasterUniversity 18:e2f92ac26450 515 }