![](/media/cache/profiles/f8936fbd065f5b9fdb3149eaba9665df.50x50_q85.jpg)
Simple program to enable me to write to a 128x64 OLED display over BLE
Dependencies: Adafruit_GFX BLE_API mbed nRF51822 SemVer
main.cpp
- Committer:
- rosterloh84
- Date:
- 2015-03-30
- Revision:
- 0:d89c10040630
- Child:
- 1:9e9c52d8270a
File content as of revision 0:d89c10040630:
/** * @file * @date 30 March 2015 * @author Richard Osterloh <richard.osterloh@gmail.com> */ #include "mbed.h" #include "BLEDevice.h" #include "UARTService.h" #include "Adafruit_SSD1306.h" #define NEED_CONSOLE_OUTPUT 1 /* Set this if you need debug messages on the console; * it will have an impact on code-size and power consumption. */ #if NEED_CONSOLE_OUTPUT #define DEBUG(STR) { if (uartServicePtr) uartServicePtr->writeString(STR); } #else #define DEBUG(...) /* nothing */ #endif /* #if NEED_CONSOLE_OUTPUT */ BLEDevice ble; DigitalOut led1(LED1); DigitalOut led2(LED2); DigitalOut led3(LED3); DigitalOut led4(LED4); InterruptIn btn1(BUTTON1); DigitalOut oled_gnd(p3); // an I2C sub-class that provides a constructed default class I2CPreInit : public I2C { public: I2CPreInit(PinName sda, PinName scl) : I2C(sda, scl) { oled_gnd = 0; frequency(400000); start(); }; }; I2CPreInit gI2C(p5, p4); // SDA, SCL Adafruit_SSD1306_I2c gOled(gI2C, p2, 0x78, 64, 128); // I2C, RST, ADDRESS, WIDTH, HEIGHT bool rxPayloadUpdated = false; const static unsigned MAX_SIZEOF_RX_PAYLOAD = 20; char rxPayload[MAX_SIZEOF_RX_PAYLOAD] = {0,}; UARTService *uartServicePtr; const char *deviceName = "BLE DISPLAY"; /** * Callback to write to connected client and display */ void buttonCallback(void) { if(btn1) { gOled.clearDisplay(); gOled.printf("%s", "BTN 0 released"); gOled.display(); uartServicePtr->writeString("Button 0 released\r\n"); } else { gOled.clearDisplay(); gOled.printf("%s", "BTN 0 pressed"); gOled.display(); uartServicePtr->writeString("Button 0 pressed\r\n"); } } /** * Callback when new client connects to device * * @param tHandle handle to this specific client * @param ePeerAddrType the type of the connected clients address * @param c6PeerAddr the address of the connected client * @param params requested connection parameters */ void connectionCallback(Gap::Handle_t tHandle, Gap::addr_type_t ePeerAddrType, const Gap::address_t c6PeerAddr, const Gap::ConnectionParams_t *params) { //DEBUG("CONNECT: Handle:%u, eType:%d, Add:%u\r\n", tHandle, ePeerAddrType, c6PeerAddr); //DEBUG(" minInterval:%d, maxInterval:%d, latency:%d, timeout:%d\r\n", // params->minConnectionInterval, params->maxConnectionInterval, params->slaveLatency, params->connectionSupervisionTimeout); DEBUG("CONNECTED\r\n"); led2 = 1; led4 = 0; } /** * Callback called when a client disconnects * * @param tHandle handle of the disconnected client * @param eReason the reason they disconnected */ void disconnectionCallback(Gap::Handle_t handle, Gap::DisconnectionReason_t reason) { DEBUG("Disconnected!\n\r"); DEBUG("Restarting the advertising process\n\r"); ble.startAdvertising(); led2 = 0; led4 = 1; } /** * Callback called when a client writes to this device * * @param params all parameters related to this data */ void onDataWritten(const GattCharacteristicWriteCBParams *params) { if ((uartServicePtr != NULL) && (params->charHandle == uartServicePtr->getTXCharacteristicHandle())) { uint16_t bytesRead = params->len; if (bytesRead < MAX_SIZEOF_RX_PAYLOAD) { strncpy(rxPayload, (const char *)params->data, MAX_SIZEOF_RX_PAYLOAD - 1); rxPayload[bytesRead] = '\0'; rxPayloadUpdated = true; ble.updateCharacteristicValue(uartServicePtr->getRXCharacteristicHandle(), params->data, bytesRead); } } } void periodicCallback(void) { led1 = !led1; /* Do blinky on LED1 while we're waiting for BLE events */ } int main(void) { led1 = 1; led2 = 1; led3 = 1; led4 = 1; Ticker ticker; ticker.attach(periodicCallback, 1); btn1.fall(buttonCallback); btn1.rise(buttonCallback); DEBUG("Initialising the nRF51822\n\r"); ble.init(); ble.onConnection(connectionCallback); ble.onDisconnection(disconnectionCallback); ble.onDataWritten(onDataWritten); /* setup advertising */ ble.accumulateAdvertisingPayload(GapAdvertisingData::BREDR_NOT_SUPPORTED); ble.setAdvertisingType(GapAdvertisingParams::ADV_CONNECTABLE_UNDIRECTED); ble.accumulateAdvertisingPayload(GapAdvertisingData::SHORTENED_LOCAL_NAME, (const uint8_t *)deviceName, strlen(deviceName)); /*ble.accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LIST_128BIT_SERVICE_IDS, (const uint8_t *)UARTServiceUUID_reversed, sizeof(UARTServiceUUID_reversed));*/ ble.setAdvertisingInterval(160); /* 100ms; in multiples of 0.625ms. */ ble.startAdvertising(); UARTService uartService(ble); uartServicePtr = &uartService; while (true) { if (rxPayloadUpdated) { gOled.clearDisplay(); gOled.printf("%s", rxPayload); gOled.display(); rxPayloadUpdated = false; } ble.waitForEvent(); } }