Rob Dobson
Using the MBED BLE library and Nordic Puck library this is a simple scoring application using Bluetooth LE. It monitors three analog inputs and triggers on reception of a pulse on any one recording data for a short period on all three. This is then published via BLE characteristics. It's a demonstrator for a new UI dev toolkit that is under development.
Fork of
Example_Puck_BLE
by 
Nordic Semiconductor
Revision 3:a155da1cbde3, committed 2014-08-21
- Comitter:
- Bobty
- Date:
- Thu Aug 21 11:26:26 2014 +0000
- Parent:
- 2:e400fd4f501b
- Child:
- 4:cc164ecf6a36
- Commit message:
- Working but misses some quick pulses (thows)
Changed in this revision
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/SampleChannel.cpp Thu Aug 21 11:26:26 2014 +0000
@@ -0,0 +1,142 @@
+// Simple averaging filter
+#include "mbed.h"
+#include "UUID.h"
+#include "SampleChannel.h"
+
+SampleChannel::SampleChannel(PinName pin, const UUID uuid, Serial* pLogger) : chanUuid(uuid), ain(pin)
+{
+ pLocalLogger = pLogger;
+ for (int i = 0; i < NUM_FILTER_VALS; i++)
+ filterBuf[i] = 0;
+ curFilterIdx = 0;
+ for (int i = 0; i < NUM_RETURN_SAMPLES; i++)
+ sampleBuf[i] = 0;
+ curSampleIdx = 0;
+ isCapturing = false;
+ sampleThreshold = 100;
+ sampleDivisor = 10;
+ testSampleCount = 0;
+ sampleBaseVal = 0;
+}
+
+void SampleChannel::SetThreshold(uint16_t threshold)
+{
+ sampleThreshold = threshold;
+}
+
+void SampleChannel::SetDivisor(uint16_t divisor)
+{
+ sampleDivisor = divisor;
+}
+
+void SampleChannel::AddSample(uint16_t val)
+{
+ testSampleCount++;
+ if (testSampleCount == 100)
+ {
+ pLocalLogger->printf("%d AvgT %d, AvgW %d, low %d\n", val, GetAvgOfTriggerWindow(), GetAvgOutsideTriggerWindow(), GetLowest());
+ testSampleCount = 0;
+ }
+
+ // If capturing add to sample buf
+ if (isCapturing)
+ {
+ if (curSampleIdx < NUM_RETURN_SAMPLES)
+ {
+ int mungedVal = val - sampleBaseVal;
+ if (mungedVal < 0)
+ mungedVal = 0;
+ mungedVal = mungedVal / sampleDivisor;
+ if (mungedVal > 255)
+ mungedVal = 255;
+ sampleBuf[curSampleIdx++] = (uint8_t)mungedVal;
+ }
+ }
+ // Add to filter
+ filterBuf[curFilterIdx] = val;
+ curFilterIdx++;
+ curFilterIdx = curFilterIdx % NUM_FILTER_VALS;
+}
+
+int SampleChannel::GetAvgOutsideTriggerWindow()
+{
+ int sum = 0;
+ for (int i = 0; i < NUM_FILTER_VALS-TRIGGER_WINDOW; i++)
+ sum += filterBuf[(i + curFilterIdx) % NUM_FILTER_VALS];
+ return sum / (NUM_FILTER_VALS - TRIGGER_WINDOW);
+}
+
+int SampleChannel::GetAvgOfTriggerWindow()
+{
+ int sum = 0;
+ for (int i = 0; i < TRIGGER_WINDOW; i++)
+ sum += filterBuf[(curFilterIdx + NUM_FILTER_VALS - 1 - i) % NUM_FILTER_VALS];
+ return sum / TRIGGER_WINDOW;
+}
+
+uint16_t SampleChannel::GetLowest()
+{
+ uint16_t lowVal = 0xffff;
+ for (int i = 0; i < NUM_FILTER_VALS; i++)
+ if (lowVal > filterBuf[i])
+ lowVal = filterBuf[i];
+ return lowVal;
+}
+
+void SampleChannel::Service()
+{
+ // take a sample and add to trigger buffer
+ unsigned short val = ain.read_u16();
+ AddSample(val);
+}
+
+bool SampleChannel::IsSampling()
+{
+ return isCapturing;
+}
+
+bool SampleChannel::AreSamplesReady()
+{
+ // Check if sample ready
+ return (isCapturing && (curSampleIdx == NUM_RETURN_SAMPLES));
+}
+
+void SampleChannel::StopSampling()
+{
+ isCapturing = false;
+}
+
+void SampleChannel::StartSampling()
+{
+ curSampleIdx = 0;
+ isCapturing = true;
+ sampleBaseVal = GetLowest();
+
+ // Copy across values from trigger window
+ for (int i = TRIGGER_WINDOW; i > 0; i--)
+ AddSample(filterBuf[(curFilterIdx + NUM_FILTER_VALS - i) % NUM_FILTER_VALS]);
+}
+
+bool SampleChannel::CheckTrigger()
+{
+ // Check if the samples in the trigger window are significantly different from the average
+ for (int i = 0; i < TRIGGER_WINDOW; i++)
+ {
+ int spike = GetAvgOfTriggerWindow() - GetAvgOutsideTriggerWindow();
+ if (spike < 0)
+ spike = -spike;
+ return (spike > sampleThreshold);
+ }
+ return false;
+}
+
+uint8_t *SampleChannel::GetSamples()
+{
+ return sampleBuf;
+}
+
+int SampleChannel::GetSamplesLen()
+{
+ return NUM_RETURN_SAMPLES;
+}
+
\ No newline at end of file
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/SampleChannel.h Thu Aug 21 11:26:26 2014 +0000
@@ -0,0 +1,46 @@
+
+#ifndef __SampleChannel__H__
+#define __SampleChannel__H__
+
+const int NUM_FILTER_VALS = 10;
+const int TRIGGER_WINDOW = 3;
+const int NUM_RETURN_SAMPLES = 20;
+
+class SampleChannel
+{
+ private:
+ UUID chanUuid;
+ uint16_t sampleThreshold;
+ uint16_t sampleDivisor;
+ uint16_t filterBuf[NUM_FILTER_VALS];
+ int curFilterIdx;
+ uint8_t sampleBuf[NUM_RETURN_SAMPLES];
+ int curSampleIdx;
+ bool isCapturing;
+ void AddSample(uint16_t val);
+ AnalogIn ain;
+ int GetAvgOutsideTriggerWindow();
+ int GetAvgOfTriggerWindow();
+ uint16_t GetLowest();
+ Serial* pLocalLogger;
+ int testSampleCount;
+ uint16_t sampleBaseVal;
+
+ public:
+ SampleChannel(PinName pin, const UUID uuid, Serial* pLogger);
+ void SetThreshold(uint16_t threshold);
+ void SetDivisor(uint16_t divisor);
+ void Service();
+ bool IsSampling();
+ bool AreSamplesReady();
+ void StopSampling();
+ void StartSampling();
+ bool CheckTrigger();
+ uint8_t *GetSamples();
+ int GetSamplesLen();
+ UUID GetUUID() {
+ return chanUuid;
+ }
+};
+
+#endif
\ No newline at end of file
--- a/main.cpp Thu Aug 21 07:48:18 2014 +0000
+++ b/main.cpp Thu Aug 21 11:26:26 2014 +0000
@@ -7,37 +7,32 @@
#define LOG_LEVEL_INFO
#include "Puck.h"
+#include "SampleChannel.h"
Puck* puck = &Puck::getPuck();
// Gatt characteristic and service UUIDs
const UUID SCORING_GATT_SERVICE = stringToUUID("nod.score1.serv ");
-const UUID SAMPLES_GATT_CHARACTERISTIC = stringToUUID("nod.score1.samp1");
const UUID THRESHOLD_GATT_CHARACTERISTIC = stringToUUID("nod.score1.thres");
-const UUID OFFSET_GATT_CHARACTERISTIC = stringToUUID("nod.score1.offs ");
const UUID DIVISOR_GATT_CHARACTERISTIC = stringToUUID("nod.score1.div ");
const UUID INTERVAL_US_GATT_CHARACTERISTIC = stringToUUID("nod.score1.intus");
-const int SAMPLES_LEN = 20;
-uint8_t SAMPLES_BUF[SAMPLES_LEN];
-
-// Sample threshold
-uint16_t sampleThreshold = 800;
-
-// Sample offset
-uint16_t samplesOffset = 760;
-
-// Sample divisor
-uint16_t samplesDivisor = 1;
+const int NUM_SAMPLE_CHANNELS = 1;
// Sample interval (uS)
-uint32_t sampleIntervalUs = 10000;
+uint32_t sampleIntervalUs = 100000;
-// Setup ADC
-AnalogIn ain(P0_1);
+// Sample Channels
+SampleChannel sampleChannels[] =
+{
+ SampleChannel(P0_1, stringToUUID("nod.score1.samp1"), &logger),
+ SampleChannel(P0_2, stringToUUID("nod.score1.samp2"), &logger),
+ SampleChannel(P0_3, stringToUUID("nod.score1.samp3"), &logger)
+};
// Timer to avoid repeat sampling
-Timer antiRepeatTimer;
+Timer intervalTimer;
+int lastTriggerTime = 0;
int lastSampleTime = 0;
const int MIN_MS_BETWEEN_SAMPLES = 2000;
@@ -45,28 +40,24 @@
{
uint16_t threshold = value[0] * 256 + value[1];
LOG_INFO("Threshold=%d\n", threshold);
- sampleThreshold = threshold;
-}
-
-void onOffsetSet(uint8_t* value)
-{
- uint16_t offset = value[0] * 256 + value[1];
- LOG_INFO("Offset=%d\n", offset);
- samplesOffset = offset;
+ for (int chanIdx = 0; chanIdx < NUM_SAMPLE_CHANNELS; chanIdx++)
+ sampleChannels[chanIdx].SetThreshold(threshold);
}
void onDivisorSet(uint8_t* value)
{
uint16_t divisor = value[0] * 256 + value[1];
LOG_INFO("Divisor=%d\n", divisor);
- samplesDivisor = divisor;
+ for (int chanIdx = 0; chanIdx < NUM_SAMPLE_CHANNELS; chanIdx++)
+ sampleChannels[chanIdx].SetDivisor(divisor);
}
void onIntervalSet(uint8_t* value)
{
uint32_t intervalUs = (value[0] << 24) + (value[1] << 16) + (value[2] << 8) + value[3];
LOG_INFO("SampleInterval(uS)=%d\n", intervalUs);
- sampleIntervalUs = intervalUs;
+ if (intervalUs <= 1000000)
+ sampleIntervalUs = intervalUs;
}
int main(void)
@@ -76,33 +67,28 @@
logger.baud(115200);
// Add the Gatt characteristic for samples
- puck->addCharacteristic(
+ for (int chanIdx = 0; chanIdx < NUM_SAMPLE_CHANNELS; chanIdx++)
+ {
+ puck->addCharacteristic(
SCORING_GATT_SERVICE,
- SAMPLES_GATT_CHARACTERISTIC,
- SAMPLES_LEN,
+ sampleChannels[chanIdx].GetUUID(),
+ sampleChannels[chanIdx].GetSamplesLen(),
GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_READ | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_NOTIFY);
+ }
// Add the Gatt characteristic for threshold
puck->addCharacteristic(
SCORING_GATT_SERVICE,
THRESHOLD_GATT_CHARACTERISTIC,
- sizeof(sampleThreshold),
+ sizeof(uint16_t),
GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE);
puck->onCharacteristicWrite(&THRESHOLD_GATT_CHARACTERISTIC, onThresholdSet);
- // Add the Gatt characteristic for offset
- puck->addCharacteristic(
- SCORING_GATT_SERVICE,
- OFFSET_GATT_CHARACTERISTIC,
- sizeof(samplesOffset),
- GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE);
- puck->onCharacteristicWrite(&OFFSET_GATT_CHARACTERISTIC, onOffsetSet);
-
// Add the Gatt characteristic for sample divisor
puck->addCharacteristic(
SCORING_GATT_SERVICE,
DIVISOR_GATT_CHARACTERISTIC,
- sizeof(samplesDivisor),
+ sizeof(uint16_t),
GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE);
puck->onCharacteristicWrite(&DIVISOR_GATT_CHARACTERISTIC, onDivisorSet);
@@ -118,37 +104,67 @@
puck->init(0xCD01);
// Start timer
- antiRepeatTimer.start();
+ intervalTimer.start();
// Wait for something to be found
- while(puck->drive())
+ while(true)
{
- int curTimerVal = antiRepeatTimer.read_ms();
- if ((lastSampleTime < curTimerVal) || (curTimerVal - lastSampleTime > MIN_MS_BETWEEN_SAMPLES))
+ // service all channel's state machines
+ bool isAnyChannelSampling = false;
+ for (int chanIdx = 0; chanIdx < NUM_SAMPLE_CHANNELS; chanIdx++)
{
- // Check threshold
- unsigned short val = ain.read_u16();
- if(val > sampleThreshold)
+ sampleChannels[chanIdx].Service();
+ if (sampleChannels[chanIdx].AreSamplesReady())
{
- for (int i = 0; i < SAMPLES_LEN; i++)
+ // Set the value of the characteristic
+ puck->updateCharacteristicValue(sampleChannels[chanIdx].GetUUID(), sampleChannels[chanIdx].GetSamples(), sampleChannels[chanIdx].GetSamplesLen());
+ sampleChannels[chanIdx].StopSampling();
+ LOG_INFO("StopSampling\n");
+ }
+ if (sampleChannels[chanIdx].IsSampling())
+ isAnyChannelSampling = true;
+ }
+
+ if (!isAnyChannelSampling)
+ {
+ // Service the puck
+ puck->drive();
+
+ int curTimerVal = intervalTimer.read_ms();
+ if ((lastTriggerTime < curTimerVal) || (curTimerVal - lastTriggerTime > MIN_MS_BETWEEN_SAMPLES))
+ {
+
+ // check each channel to see if it's been triggered
+ bool anythingTriggered = false;
+ for (int chanIdx = 0; chanIdx < NUM_SAMPLE_CHANNELS; chanIdx++)
{
- SAMPLES_BUF[i] = (ain.read_u16() - samplesOffset) / samplesDivisor;
- wait_us(sampleIntervalUs);
+ if (sampleChannels[chanIdx].CheckTrigger())
+ {
+ anythingTriggered = true;
+ LOG_INFO("Triggered\n");
+ break;
+ }
}
-
- // Set the value of the characteristic
- puck->updateCharacteristicValue(SAMPLES_GATT_CHARACTERISTIC, SAMPLES_BUF, SAMPLES_LEN);
-
- // Display readings
- for (int j = 0; j < SAMPLES_LEN; j++)
+ if(anythingTriggered)
{
- LOG_INFO("%02x ", SAMPLES_BUF[j]);
+ for (int chanIdx = 0; chanIdx < NUM_SAMPLE_CHANNELS; chanIdx++)
+ {
+ sampleChannels[chanIdx].StartSampling();
+ }
+ // Set timer to disallow repeated readings
+ lastTriggerTime = curTimerVal;
}
- LOG_INFO("\n");
+ }
+ }
+ else
+ {
+ wait_us(sampleIntervalUs);
+ }
- // Set timer to disallow repeated readings
- lastSampleTime = curTimerVal;
- }
- }
+ // Inter-sample interval
+ //while ((intervalTimer.read_us() - lastSampleTime < sampleIntervalUs) && (intervalTimer.read_us() - lastSampleTime > 0))
+ // wait_us(100);
+// lastSampleTime = intervalTimer.read_us();
+// LOG_INFO("Timer %d\n", intervalTimer.read_ms());
}
}