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Serial, mbed, compiler, ethernet, USB, I2C, SPI, interrupt, LCD, library, bug, HTTPServer, CAN, AnalogIn, adc, Power, Ticker, memory, pwm, SD Card, InterruptIn, rpc, Error, SDFileSystem, PwmOut, LocalFileSystem, UART, canbus, driver, TCP, interrupts, rtos, led, libraries, editor, timer, accelerometer, GPS, file, clock, website, C++, SD, frequency, reset, http, LPC11U24, flash, SDCard, RTC, DigitalIn, TCPSocket, problem, printf, Java, Servo, buffer, UDP, SerialPC, DMA, HTTPClient, Sleep, audio, pinball, MODSERIAL, NetServices, socket, array, compile, filesystem, RFID, beta, m3pi, write, LPC1768, multiple, newbie, keyboard, sensor, GPRS, Forum, digitalOut, assembly, debug, hardware, Speed, xbee, AnalogOut, RPCFunction, EthernetNetIf, Download, code, voltage, wait, network, C, suggestion, JTAG, keil, MATLAB, offline, Board, lwip, I2S, dead, Nokia6610, time, bluetooth, WiFly, current, tcp/ip, MODDMA, SPI Slave, pololu, robot, Communication, read, dac, string, pc, binary, filter, copy, USB Host, publish, rs232, DHCP, Host, Data Logging, windows, firmware, malloc, mp3, PCB, gcc, attach, program, fatfilesystem, class, email, arduino, stepper motor, WavePlayer, wifi, Nokia, camera, size, VGA, import, documentation, ide, linux, baud, TextLCD, Cortex-M0, M0, pointers, pullup, Relay, timing, function, latency, serial port, MIDI, compiler error codes, magjack, touch, screen, Production, client, server, stream, HID, breakout, FIFO, prototype, flashing, GPIO, sampling, Analog, display, api, ADXL345, Encoder, DSP, help, motor, sram, suggestions, PING, Terminal, link, browser, Pin, control, Eagle, Modbus, EEPROM, mac, Timeout, fopen, port, updates, usbserial, batteries, DMX, files, USBMIDI, scanf, protocol, PPP, slave, FTP, integer, noise, MODGPS, modem, float, threads, motors, for, monitor, Digital I/O, 7, Windows Serial Driver, pins, keypad, FAT, classes, webserver, delay, variables, time-triggered, c programming, labview, watchdog, post, math, Battery, LPCXpresso, MBED website, GSM, storage, nxp, mobileLCD, license, int, counter, baseboard, Assembler, Vin, rj45, registers, E289, news, i2cmaster, amoled, Compiling, connect, revision, prototype to hardware, UMTSStick, Optocoupler, Robotics, search, oscillator, glitch, Websockets, load, find, real-time, routine, format, offline compile, powersource, driverlibrary, processing, networking, ID, umts, debugging, color, BUTTON, software, PS3, Images, wave, bin, const, SNMP, OSX, supply, peripheral, sensors, data, Design, PID, version, RIT, character, freeze, USBDevice, bus, ARM, wav, SRF08, heap, output, basic, TFT, QVGA, mysql, piezo, update, ID12, Pachube, player, DigitalInOut, object, cmsis, capture, IR, slow, 1768, PSP, OS, syntax, mbed.lib, EmbeddedArtists, NMEA, paste, project, Web, GUI, UART0, firefox, SQL, wakeup, RAM, bitmap, handler, security, 3D, bugs, OLED, Temperature, not, I/O, Bidirectional, rss, wireless, delete, resolved, LED1, LIS302, getc, Safari, Wi-Fi, wiki, PinNames, accounts, PS2, BusOut, projects, RS485, pythonMy guess is that it fills a buffer on writing. As soon as the buffer is 'at max' it is written to the sd card causing some delay. If you add up the bytes written it might give a clue how large this buffer is (probably 512 or 2048 bytes, aka sector size?)
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Hi,
I just noticed a funny pattern where every 7th message takes around 6000us, while every other message takes around 35us when saving GPS strings.
Code
void task1(void) { while (1) { os.WaitEvent(TIMER0_EVENT); if (readLine < printLine) { pc.printf("%s\r\n", gpsTEMP[readLine]); t.start(); fprintf(gps, "\n\r%s", gpsTEMP[readLine]); // readLine++; t.stop(); printf("TIME: %d\r\n", t.read_us()); t.reset(); if (readLine == printLine) { // pc.printf("\n\n\r RESET COUNTERS \n\n\r"); readLine =0; printLine = 0; } else { os.SetEvent(TIMER0_EVENT, TASK1_ID); } } } }Output:
Code
Any ideas as to what could be causing this?
Thanks, Sebastian