Did you try this: edit yes you tried it. System time can be kept by using either one or both of the hardware timers depending on the application’s purpose and accuracy requirements for system time. When you do delay (1000) your Arduino stops on that line for 1 second. Sets how quickly the timer counter is “ticking”. h to make the microsecond timer call visible. ticks_ms (), start) # compute time difference. Hello community,Re: small numbers of µS delays. Certain things do go on while the delay () function is controlling the Atmega chip, however, because the delay function does not disable interrupts. 0. The LED should turn on for 20 seconds when motion is detected, and a message should be printed in the Shell. For delays longer than a few thousand microseconds, you should use delay() instead. Functions. vTaskDelay(500 / portTICK_RATE_MS); You can use vTaskDelay () even if not using FreeRTOS tasks. Then I thought to make the delay smaller so I changed delay(1) to delayMicroseconds(100) and it did crash again. For a full example, refer to PlatformIO ESP-IDF ESP32 blink. 0) usleep (100) #sleep during 100μs. Servo - writeMicroseconds () Writes a value in microseconds (us) to the servo, controlling the shaft accordingly. Neopixels have great possibilties. Then post here. delay() – Busyloops the processor for a specified number of microseconds. Delay and timing¶ Use the time module: import time time. $egingroup$ Apologies Steven, I sincerely thought (and think) it's a good way to express the question succinctly and clearly. Minimally, the current behavior ought to be documented and perhaps its use discouraged for all but very short delays. For microseconds based delay, DWT cycle counter is used to get maximal optimized delay. Your new topic does not fit any of the above??? Check first. ticks_diff ( time . Version 1. In pseudocode it will look like this:By default, the baud rate of esp8266 is 115200. add both files in the project. There are a thousand microseconds in a millisecond and a million microseconds in a second. attach (9); To move the servo arm, you use the servo. The Arduino delayMicroseconds () function is a built-in function that pauses the CPU for a short time interval (in µs). e. g. filo_gr Posts: 109 Joined: Wed Jul 28, 2021 12:25 pm Location: Italy [SOLVED] My function for microseconds delay doesn't work properly. I encountered the following problem when using it: if I use a value such as delay_us(20), it doesn't work! Driving a pin (from high to low and vice. Blinking leds pattern using 89c51 microcontroller. 1. However, be aware that micros. 1inches), which is good for most hobbyist projects. 1 hour in microseconds is 3600000000UL. Replaced the folder mentioned in point 3 with the Ticker folder in point 2. . For ESP-IDF, you can use this: Code: Select all. Returns. system_deep_sleep (0): there is no wake up timer; in order to wake up, connect a. 3V Vcc (Vcc cannot exceed 3. ESP8266 Report Bugs Showcase; Chinese Forum 中文社区 活动区 乐鑫活动专区 讨论区 ESP-IDF 中文讨论版 《ESP32-C3 物联网工程开发实战》书籍讨论版 ESP-AT 中文讨论版 ESP-BOX 中文讨论版 ESP IoT Solution 中文讨论版 ESP-ADF 中文讨论版 Description. light sleep: the necessary steps to enter timed sleep are a bit fickle, so read this closely (see esp8266/Arduino#7055 for more details): timer-based light sleep can be between ~10. begin (115200) ESP8266. 41 6 6 bronze badges. When ı create a task using xTaskCreate() function and adding some delay in the task function. delay(ms) pauses the sketch for a given number of milliseconds and allows WiFi and TCP/IP tasks to run. Note that some manufactures do not follow this. uint64_t microseconds = esp_timer_get_time (); // Starting the count, it exits. tmr. Re: yield () and delay () best practices #73704. I dont get any delay even if I add some different delays. I’ve updated my delay library to support milliseconds and microseconds delays. For microseconds based delay, DWT cycle counter is used to get maximal optimized delay. Download the latest ticker package as a zip file. cpp: AHT10_DEFAULT_DELAY = 8 and AHT10_HUMIDITY_DELAY = 40. It does some delay + gpio, and measures the timing using ccount. Interrupts on ESP32 are soft IRQ's and are subject to latency which can run to milliseconds, especially on SPIRAM boards, On a Pyboard latency is on the order of 15μs. We have set the period as 5000ms which means 5 seconds. LAC timer is used for ESP32. Re: vTaskDelay () vS. In addition, it is not possible to execute delay() or yield() from an ISR, or do blocking operations, or operations that disable the interrupts, e. ticks_ms ¶ Then I assumed it's too fast so I added delay(1) in the loop and no crash occured anymore (code#2). According to the features used by an application, there are some sub sleep modes. . h> #include <ESP8266WiFi. Timer (0)Having the ESP8266 add-on for the Arduino IDE installed ( How to Install the ESP8266 Board in Arduino IDE ). Why does this work? Adding delay (1) actually causes the CPU to spend the vast majority of its time in that one millisecond loop. To put the ESP8266 in deep sleep mode for an indefinite period of time use ESP. micros = running microseconds millis = running milliseconds loglvl = loglevel of script cmds (may be set also). . cpp","contentType":"file. We can use the machine. Hello community,delay() in main loop should be avoided on esp8266/arduino. Each time a person taps a card to the MFRC522 reader module, it will send the UID for. Make sure you connect the following wires from the stepper motor to their corresponding pins on the A4988 driver: What does this implement/fix? This is a refactor of Remote transmitter for ESP8266 to provide more accurate timing. hw_timer_t * timerBegin(uint32_t frequency); frequency select timer frequency in Hz. The delayMicroseconds () won't let me control multiple lamps, so I want to replace it with micros () (code below). ticks_ms ¶Then I assumed it's too fast so I added delay(1) in the loop and no crash occured anymore (code#2). if we write delayMicroseconds(1000), then the delay will be of 1000 microseconds i. IoT Live Weather Station. 5) nRF52 (tested on nRF52832)I was looking for a simple a way to delay switching on the edge detecting side but I couldn't find out how. val: the value to print. Your main. On the ESP32, the bootrom is much bigger (7*64k) than on the ESP8266: ROM0 - 0x4000 0000 to 0x4006 ffff. The timing of these timers depends upon the clock and varies from one board to the other. 2 (depending on compiler settings)ESP8266 - NodeMCU - CPU Speed Test: Simply put, faster CPUs complete more calculations, more lines of code and more house keeping tasks in a given period of time. 本指南展示了如何使用Arduino IDE与ESP8266（NodeMCU）一起使用深度睡眠。我们将使用定时器唤醒来唤醒深度睡眠，并使用复位（RST）引脚来唤醒外部唤醒。引入深度睡眠模式如果您使用电池供电的ESP8266板制作了一个项目，或者只是将ESP8266 NodeMCU板连接到了移动电源。1. I measured the following delays in CPU ticks (80 MHz): delayMicroseconds (1) : 130 ticks, 50 ticks too much delayMicroseconds (2) : 202 ticks, 42 ticks too much delayMicroseconds (3) : 286 ticks, 46 ticks too much delayMicroseconds (4) : 370 ticks, 50 ticks too much delayMicroseconds. This function create a square wave PWM signal. Code. c or main. Delay functions. Replaced the folder mentioned in point 3 with the Ticker folder in. Click the tab to view its contents, including detailed descriptions of the available. 6. For microseconds based delay, DWT cycle counter is used to get maximal optimized delay. You start the delay and then. Running a number of times or forever. Share. Actually, we have connected one module over UART with ESP32 chip in our product. On the ESP8266 the time between edges on the input and output pins is about 140us and very consistent. It is microseconds and not milliseconds. Instead of programming delays inside of an infinite loop, a periodic timer with a callback can achieve the same outcome while also allowing other processes to run. Functions. Not sure why it says error but I'm quite certain that. sleep_us (us) ¶ Delay for given number of microseconds, should be positive or 0. 6) 4ch Home Automation With IR. Your new topic does not fit any of the above??? Check first. so they do not have round trip delay into account. For the Arduino and ESP8266 boards we use the A0 pin and for the ESP32 we define pin 4 as analog input. Go to left sidebar of the IDE, click the “ New file ” button and it will create a new file and it will open with in editor window as a untitled name. สวัสดีครับ ท่านที่พึ่งหัดเขียนโปรแกรมแรกๆ มักจะได้เรียนรู้ delay กันไปแล้วแน่นอน อย่างน้อยก็ Example blink แหละนะ ฟังก์ชัน delay เป็นการหยุดรอเท่าจำนว. I started to write simple code to read null terminated strings using client. delay(ms) pauses the sketch for a given number of milliseconds and allows WiFi and TCP/IP tasks to run. delay(ms) pauses the sketch for a given number of milliseconds and allows WiFi and TCP/IP tasks to run. read () with simple timeout functionality. println (sensorValue); vTaskDelay ( 1 ); // one tick delay (15ms) in. In a more advanced system that is using a real-time operating system (RTOS), developers can leverage built in RTOS API calls for yielding a task to create a delay. #18 สอนใช้งาน Arduino tracking sensor TCRT5000 ตรวจจับเส้นขาวดำ. The ESP8266EX microcontroller integrates a Tensilica L106 32-bit RISC processor, which achieves extra-low power consumption and reaches a maximum clock speed of 160 MHz. To enable sleep there must be delay after wifi_fpm_do_sleep which must be at least +1 longer than setted sleep duration. Look for ESP8266 by ESP8266 Community. The arduino delay () function creates a blocking delay of the provided number of milliseconds. Syntax – delay (ms) delay function takes only one argument, Which will be the amount of time we have to pause the code. Should we use "delay()" as we don't want the 25 microseconds to be interrupted. com Why does this work? Adding delay (1) actually causes the CPU to spend the vast majority of its time in that one millisecond loop. ticks_us ¶ Just like ticks_ms above, but in microseconds. Serial communication that appears. first of all, many thanks for this great library and toolset for ArduinoIDE to work with ESP8266. EVERY_N_MILLISECONDS is the right thing to do (similar to the BlinkPolledTimeout example in the arduino IDE). int outPin = 8; // digital pin 8 void setup() { pinMode(outPin, OUTPUT); // sets the digital pin as output } void loop() { digitalWrite(outPin, HIGH); // sets the pin on. The supported way to use WebREPL is by connecting to ESP8266 access point, but. @jsotola wireshark captures no information from the ip of the esp8266 device, udp or otherwise. millis() and micros() return the number of milliseconds and microseconds elapsed after reset, respectively. Maybe someone else finds this also useful. By defining USE_US_TIMER and using system_timer_reinit () one can get microsecond accurate timers. This could change in future Arduino releases. La función delay() pausa la ejecución de tus programas, no deberías utilizarla pues bloquea tu tarjeta, en este vídeo te. Milliseconds based delay is done using systick timer which makes interrupts every 1ms generated by HAL library. Delay for given number of microseconds, should be positive or 0. void setup() {. The timebase is the same as for the values returned by esp_timer_get. Therefore, their executions are not blocked by bad-behaving functions or. Milliseconds based delay is done using systick timer which makes interrupts every 1ms generated by HAL library. unsigned long IRAM_ATTR micros() { return ( unsigned long ). I don't see udp. ticks_ms ¶The example code works fine, delays for five seconds as long as the part in the loop is commented out, otherwise whis part lets the task resume. Using Arduino setup () and loop () In main folder open file CMakeList. Thanks. 1us = SystemCoreClock / 1000000. 3. fn_delay_us: delay in microseconds. unixway commented on Apr 25, 2018. It does not stop the buzzer after a delay timer, buzzer beeps and stops within milliseconds. The argument decides how much amount of time we want to pause the code. Dimming an LED may be done with PWM -. The value of the resistor in series with the LED may be of a different value than 200 ohm; the LED will lit up also with values up to 1K ohm. See the output in Serial Monitor. If voltage is supplied it generates beep sound. See the list of available serial ports for each board on the Serial main page. If your application requires that you constantly. This is the documentation for the latest development branch of MicroPython and may refer to features that are not available in released versions. Atmega is the controller chip. Bestimmte Dinge laufen jedoch weiter, während die delay () -Funktion den Atmega-Chip steuert, da die delay () -Funktion Interrupts nicht. 25 = 331. sleep_ms (500) # sleep for 500 milliseconds time. ESPNtpClient do not have any external dependency. Delay for given number of microseconds, should be positive or 0. millis() and micros() return the number of milliseconds and microseconds elapsed after reset, respectively. This Blynk ESP8266 control smart relay has the following features: Control home appliances with WiFi (Blynk IoT App). ticks_ms # get millisecond counter delta = time. time. ino" file to open it in your Arduino IDE. COROUTINE_DELAY_SECONDS(seconds): yields back execution for seconds. time. If you’re powering the sensor from a 3. deepSleep (), a flag is set in the RTC memory, the processor will reset after 20 seconds, and next time setup () is called. pin: the number of the pin that the servo is attached to. Repeat. Learn how to install the ESP8266 board add-on in Arduino IDE in less than 1 minute. If the handler takes more than 10 μs, you will have already passed the 20. Remember that there is a lot of code that. You should use it if you are using arduino, and also you should post in the arduino forum. It is likely that the number being passed to 'delay' is being interpreted as an int. Delay functions. Previously I used OPEN RTOS SDK and the library whic. Remember that there is a lot of code that. show() flickers the first led on my strip (16 leds total). It's important to note that the sleep time is specified in microseconds (µs). Your new topic does not fit any of the above??? Check first. 3 volts and LOW means 0 volts or ground. When I first tied this it didn't work and it appears that before you can use the microseconds calls, the system timer has to be reset in the right at the start of usercode. Arduino Code for Ultrasonic Sensor with LED. Moderator: igrr 7 posts; Page 1 of 2; 1, 2;Arduino15packagesesp8266hardwareesp82663. delayMicroseconds(us) pauses for a given number of microseconds. Delay functions. It does some delay + gpio, and measures the timing using ccount. MicroPython Timer API supports allf four hardware timers. Yet, it took a comment from a curious reader to set things in motion. If your are new to Internet of Things (IoT), learn about IoT by visiting our Internet of Things tutorial for beginners. You can control the shape of the PWM signal with the duty cycle of (value/255). ticks_diff. This would mean the delay is limited to a max of 32,767. If 0 is passed as the argument, the delay will equal the time spent executing the interrupt service routine. delayMicroseconds(us) pauses for a given number of microseconds. int64_t esp_timer_get_next_alarm (void) Get the timestamp when the next timeout is expected to occur. Problem is, when ESP wake up, it is blocked for delay duration before it can make. Instead of using incremental calls to delayMicroseconds(), accuracy is now dictated by the internal micros() clock. h. 0-beta2librariesTicker. But with WiFi sending, now and then there's a longer delay, which it logs. Now select your board in the Tools > Board menu (in our case, it’s the NodeMCU 1. Connect the stepper motor to the A4988 driver. Therefor, I read a lot, especally about xSemaphoreGiveFromISR which seems to be the most efficiant way to deal with this problem. You all should be familiar with delay() - it is a simple way of creating a program delay. The chip in an Uno or a Nano is an atmega328. Hi all, I'm solving issue with light sleep on ESP8266 (ESP-01). As you can see I measure the time between two instants using esp_timer_get_time() (this funcion returns an uint64_t with the number of microseconds starting from the power up). You will actually notice the delay in the response from the server when you call colorwipe totally at the end of the function server. cpp did the trick! Steps: 1) Add #define USE_US_TIMER at the. Even though this method erases the NodeMCU firmware from the ESP8266's flash memory, it is a straight-forward process to go back to using it! Other. Thanks. The steps to connect the Ultrasonic sensor to the board are listed below: Connect the VCC pin of HC-SRO4 to 5V of the Arduino board. Each call to print takes only a few microseconds. only needed if you want ESP8266 to be woken from DeepSleep by internal timer). Timestamp of the nearest timer event, in microseconds. 9 Answers. pdf (146 KB) with delay. The value should be treated as opaque, suitable for use only with ticks_diff(). @Juraj udp. Initializing Timer Interrupt in Raspberry Pi Pico. If you add a delay in the ISR, and the buffer of the UART gets full, it will overflow and you miss bytes. h> #include <AceTime. On Linux/Mac computers, see the instructions at the top of the ESP8266 TZ. ESP8266 D6 pin to A4988 Dir pin. This 8-bit value is appearing on the port 1. Thanks. This function attempts to provide an accurate delay of at least us microseconds, but it may take longer if the system has other higher priority processing to perform. Dimming Neopixels, Delays<Microseconds. getCycleCount () function and interrupts for the timing. The code for it is pretty straight forwardThis function is used to configure the timer. Make sure you connect the following wires from the stepper motor to their corresponding pins on the A4988 driver:This is a refactor of Remote transmitter for ESP8266 to provide more accurate timing. – mark-hahn. In my application, the ESP8266 is responsible for controlling the gate and must maintain continuous loop processing to continuously check the status of the photocells (whether the beam has been broken - if so, the circuit must stop the gate operation for safety reasons). The respective interrupt gets fired even if you don't use delays. org and display it on SSD1306 screen. We can use this value to trigger a deep sleep to keep the battery from discharging, as in the code below:void parpadeoLed () { digitalWrite (LED_BUILTIN, HIGH); delay (500); digitalWrite (LED_BUILTIN, LOW); } I suspect on the ESP8266 the delay statement is using the same timer as Ticker. ESP-NOW - Wrapper lib for ESP-NOW (See #2227) ESPAsyncTCP - Asynchronous TCP Library for ESP8266 and ESP32/31BYour new topic does not fit any of the above??? Check first. Delay a task for a given number of ticks. cpp as described below. Add a comment. @jsotola wireshark captures no information from the ip of the esp8266 device, udp or otherwise. AlfonsMittelmeyer commented on Apr 10, 2018 •edited. begin (). Ask Question. romkey. 7 (accuracy of my 'scope is only 4 digits). write () function like so:Dimming Neopixels, Delays<Microseconds. Open the Arduino serial monitor at a baud rate of 115200. h in the main file by using #include “dwt_stm32_delay. When ı create a task using xTaskCreate() function and adding some delay in the task function. GPIO get input level. It depends the purpose of the microsecond delay, and if it is a min value or not. 3cm (0. Your code in loop () will never run. Pauses the program for the amount of time (in microseconds) specified as parameter. Unsigned longs on the arduino can reach from 0 to 4,294,967,295. pin GPIO16, gpio_num should be GPIO_NUM_16 (16);Suggested change -- change "microseconds" to "milliseconds" because vTaskDelay is based on FreeRTOS time tic which is in multiple milliseconds. Similarly in delayMicroseconds() function, the parameter passed is in microseconds i. The discussion is here; the heatmaps are what convinced me that for these style of questions it pays to emphasize the operating. The delay() function expects you to give a number of milliseconds – not seconds – to sleep. The part of interest is this: startTime = micros (); while (digitalRead (capPos) == HIGH) { delayMicroseconds (1); } endTime = micros (); The while loop I want to. I dont get any delay even if I add some different delays. I edited the example code and removed all I think it is not necessary. tmr. digitalWrite (pin_no4, LOW); // triac Off. It is likely that the number being passed to 'delay' is being interpreted as an int. MicroPython Timer API supports allf four hardware timers. This library enables you to use Interrupt from Hardware Timers on an ESP8266-based board to create and output PWM to pins. Hello, I've found ticker. deepSleep (uS) and pass as argument sleep time in microseconds. ticks_diff. This sensor reads from 2cm to 400cm (0. As ESP-01 has only 2 GPIOs, only 2 loads can be controlled, here my necessity is to control one AC load in timer delay off mode. 3V. Saved searches Use saved searches to filter your results more quicklyErfahrene Programmierer vermeiden normalerweise die Verwendung von delay () für das Timing von Ereignissen, die länger als 10 Millisekunden sind, es sei denn, der Arduino-Sketch ist sehr einfach. asher sajid asher sajid. Timing and delays¶ millis() and micros() return the number of milliseconds and microseconds elapsed after reset, respectively. 3. สอนใช้งาน Arduino วัดค่าอุณหภูมิด้วย Sensor DS18B20. In the setup function we set the baud rate to 9600, that have to match the baud rate of the Arduino IDE to see the sensor values that we want to print on the serial connection between microcontroller and PC. There are a thousand microseconds in a millisecond, and a million microseconds in a second. Using the internal RTC, improving meassurement of time passage during sleep apparently includes guessing at the sleeping chip's temperature: Time keeping on the ESP8266 is technically quite challenging. The following video demonstrates the LED blinking with ESP8266 ESP12-E with Arduino. Regards, Ritesh Prajapati. Interrupts can happen during a delay () but delay () (millis ()) will not increment during an interrupt as interrupts are disabled in an ISR (Interrupt Service Routine). Even if Cortex-M has deterministic interrupt latency, this can cost up to 16 clock cycles in some Cortex-M (formerly M0+ processors). g. You should explicitly declare your delay value as an. ico24 November 18, 2021, 3:26pm 1. Both ESP8266-12E and ESP8266-07 have one ADC pin that is accessible. First setup the project from the CubeMx and right click the Application/User and select add existing files to group. Syntax. The supported way to use WebREPL is by connecting to ESP8266 access point, but. 7. The third question asks: "What about **time taken = 4 45025 ,. import time usleep = lambda x: time. 9 (ESP-12 board) ESP8266 and I also tested with Firebeetle ESP8266 board. Sleep itself working almost correctly, but there is one thing which is wery confusing. With a neopixel you can show values in between with smoothly changing colors from for instance blue. Thanks. See the RTOS Configuration documentation for more information. Remember that there is a lot of code that. right at the beginning of the user_init function in core_esp8266_main. Problem-relevant YAML-configuration entries: switch : - platform: gpio pin: 16 id: buzzer binary_sensor : - platform: pn532 uid: 06-8C-21-EC id: 'tag068C21EC' on_press : -. So, you can easily make this home automation. time. begin () is for listening, but I did try it and see no difference. The timing of these timers depends upon the clock and varies from one board to the other. Executing setTimeout takes only a few microseconds to complete. 5) 4 LED with 4 Debounce buttons. Neopixels have great possibilties. The sketch uses the callback when the time was set. com wiki) without having to use the Arduino IDE for uploading the. Code: Select all delayMicroseconds (7000); // Off cycle. Improve this answer. The timing will be calculated in microseconds. Timestamp of the nearest timer event, in microseconds. บทความ ESP8266 NodeMCU #1 สอนใช้งาน NodeMCU ESP8266 v2 ติดตั้ง NodeMCU ESP8266 ลงบน Arduino IDE #2 สอนใช้งาน NodeMCU ESP8266 v3 ติดตั้ง NodeMCU ESP8266 ลงบน Arduino IDEHere are two basic delay and timer sketches and their millisDelay library equivalents. delayMicroseconds(us) pauses for a given number of microseconds. number of microseconds since underlying timer has been started . the maximum value for a 32-bit unsigned integer is 4294967295 or 0xffffffff. one micro second at a time. 1. Note this that is the NodeMCU pin number and not the ESP8266 GPIO number. While ESP8266 sendmail needs brackets, ESP32 sendmail inserts brackets itself so you should not specify. delay(ms) pauses the sketch for a given number of milliseconds and allows WiFi and TCP/IP tasks to run. Short explanation of my project, is RFID based door security system using magnetic door lock. class Timer – control hardware timers. The solution to this problem is pretty trivial: just count the time in microseconds instead of milliseconds. More knowledgeable programmers usually avoid the use of delay () for timing of events longer than 10’s of milliseconds unless the Arduino sketch is very simple. utime. This example delays by 500ms: esp-idf-equivalent-to-arduino-delay. Remember that there is a lot of code that. In addition, this particular module comes with ultrasonic transmitter and receiver modules. This would mean the delay is limited to a max of 32,767. 3V microcontrollers like ESP8266. 295 seconds, or about 49 days. This code works fine, however I want to improve it to get to better time scales, by using the ESP. 3 volts microcontroller, so anywhere we refer HIGH means 3. gpio_num: GPIO number. register() –. timer = Timer (period=5000, mode=Timer. On AVR the delay(0) can be removed completely. What is the resolution of the micros () function on the Arduino Nano? a) 2 Microseconds. 2) Add appropriate calls to the Ticker library (attached) However it doesn't work correctly if microseconds will start rolling over at a smaller value (such as UINT32_MAX/240). delayMicroseconds(us) pauses for a given number of microseconds. servo: a variable of type Servo. After that, you can use vTaskDelay (. Problem is, when ESP wake. Delay for given number of milliseconds, should be positive or 0. So your clock processor clock should be > 1 MHZ. It is a two leg device the longer leg is positive. h, but this library uses milliseconds, I want to work a little faster. I did need a multiple MHz blink, and thus a nanosecond delay. Supports: periodic task execution (with dynamic execution period in milliseconds or microseconds – frequency of execution), number of iterations (limited or infinite number of iterations), execution of tasks in predefined sequence, dynamic change. Hence port 1 of 8051 microcontroller is fully occupied and is busy in making led’s blink. If you replace the while statement with: while (digitalRead (5)==HIGH) delay (1); Then it works as you would have expected. After 20 seconds the LED turns off.