1. TinyOS Tutorial Lesson 8 Data logging application

2. Outline Introduction The SenseLightToLog Application Logger component, interfaces, usage, and limitations The Sensing interface SenseLightToLogM.nc

3. Introduction SenseLightToLog Sensor EEPROM

4. Introduction SenseLightToLog Sensor EEPROM

5. SenseLightToLog SimpleCmd START_SENSINGREAD_LOG

6. SenseLightToLog (cont.) Logger Main StdControl SenseLightToLogM StdControl ADC Leds TimerC Timer SubControl Photo SubControl LoggerWriteADC LoggerWrite Comm SubControl Timer LedsC Leds Sensing

7. Logger About the EEPROM on Mica/Mica/Mica2Dot:  512 kbyte  may be read and written in 16-byte blocks, called lines  split-phase operations treating the EEPROM as a circular buffer - by maintaining an internal pointer to the next EEPROM line does not read or write data at the beginning of the EEPROM

8. Logger - LoggerRead readNext(buffer) - Read the next line from the log read(line, buffer) - Read an arbitrary line from the log resetPointer() - Set the current line pointer to the beginning of the log setPointer(line) - Set the current line pointer to the given line

9. Logger - LoggerWrite append(buffer) - Append data to the log write(line, buffer) - Write data to the log at the given line resetPointer() - Set the current line pointer to the beginning of the log setPointer(line) - Set the current line pointer to the given line

10. Logging performance high-frequency sampling - ByteEEPROM

11. SenseLightToLogM 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 data[ maxdata * 2 ] (maxdata = 8) head bufferPtr[0] bufferPtr[1] buffer0 buffer1 currentBuffer = 0 head = 0 currentBuffer = 0 head = 7 currentBuffer = 1 head = 0

12. SenseLightToLogM.nc(1/8) module SenseLightToLogM { provides interface StdControl; provides interface Sensing; uses { interface ADC; interface StdControl as SubControl; interface Leds; interface Timer as Timer; interface LoggerWrite; interface ProcessCmd as CmdExecute; }

13. SenseLightToLogM.nc(2/8) implementation { enum { maxdata = 8 }; char head; uint8_t currentBuffer; int data[maxdata*2]; int *bufferPtr[2]; short nsamples;

14. SenseLightToLogM.nc(3/8) command result_t StdControl.init() { atomic { head = 0; currentBuffer = 0; bufferPtr[0] = &(data[0]); bufferPtr[1] = &(data[8]); } return rcombine(call SubControl.init(), call Leds.init()); }

15. SenseLightToLogM.nc(4/8) command result_t StdControl.start() { return call SubControl.start(); } command result_t StdControl.stop() { return call SubControl.stop(); } command result_t Sensing.start(int samples, int interval_ms) { nsamples = samples; call Timer.start(TIMER_REPEAT, interval_ms); return SUCCESS; }

16. SenseLightToLogM.nc(5/8) event result_t Timer.fired() { nsamples--; if (nsamples== 0) { call Timer.stop(); signal Sensing.done(); } call Leds.redToggle(); call ADC.getData(); return SUCCESS; }

17. SenseLightToLogM.nc(6/8) default event result_t Sensing.done() { return SUCCESS; } task void writeTask() { char* ptr; atomic { ptr = (char*)bufferPtr[currentBuffer]; currentBuffer ^= 0x01; } call LoggerWrite.append(ptr); }

18. SenseLightToLogM.nc(7/8) async event result_t ADC.dataReady(uint16_t this_data){ atomic { int p = head; bufferPtr[currentBuffer][p] = this_data; head = (p+1); if (head == maxdata) head = 0; if (head == 0) { post writeTask(); } return SUCCESS; }

19. SenseLightToLogM.nc(8/8) event result_t LoggerWrite.writeDone( result_t status ) { //if (status) call Leds.yellowOn(); return SUCCESS; } event result_t CmdExecute.done(TOS_MsgPtr pmsg, result_t status ) { return SUCCESS; }