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  3. or cleaner: String DisplayString = " "; //a blank string int percent1 = 0; int OldPercent = 0; void setup() { // Serial.begin(9600); //testing } void loop() { if( OldPercent != percent1 ) //do not scroll needlessly { //previous string - set the cursor to second line LCD.setCursor(0,2); LCD.print(DisplayString); //move previous line down //set the cursor to for new first line LCD.setCursor(0,1); if (percent1 > 50) { //new string DisplayString = "Moisture S1 : " + String(percent1) + "%" + " Irrigaion sistem ON"; } else { //new string DisplayString = "Moisture S1 : " + String(percent1) + "%" + " Irrigaion sistem OFF"; } //set the cursor for new first line LCD.setCursor(0,1); LCD.print(DisplayString); //new line to top of the LCD OldPercent = percent1; //set new percent } } //end loop the first "set the cursor for new first line" code is redundant; I can not see how to edit the code
  4. Perhaps: String DisplayString = " "; //a blank string int percent1 = 0; int OldPercent = 0; void setup() { // Serial.begin(9600); //testing } void loop() { if( OldPercent != percent1 ) //do not scroll needlessly { //previous string - set the cursor to second line LCD.setCursor(0,2); LCD.print(DisplayString); //moves previous line down if (percent1 > 50) { //new string DisplayString = "Moisture S1 : " + String(percent1) + "%" + " Irrigaion sistem ON"; //set the cursor to for new first line LCD.setCursor(0,1); LCD.print(DisplayString); //new line to top of the LCD OldPercent = percent1; //set new percent } else { //new string DisplayString = "Moisture S1 : " + String(percent1) + "%" + " Irrigaion sistem OFF"; //set the cursor to new first line LCD.setCursor(0,1); LCD.print(DisplayString); //new line to top of the LCD OldPercent = percent1; //set new percent } } } //end loop
  5. If you want to help me, i have some questions. I want to scroll just a single line of a 20x4 display. on this line i want to write a string , then a value and at least another string. The last string will be change by a condition like this if (percent1 > 50) { LCD.setCursor(0,1); LCD.print("Moisture S1: "); LCD.print(percent1); LCD.print("%"); LCD.print(" "); LCD.print(" Irrigation sistem OFF"); LCD.print(" "); } else { LCD.setCursor(0, 1); LCD.print("Moisture S1: "); LCD.print(percent1); LCD.print("%"); LCD.print("Irrigaion sistem ON"); LCD.print(" "); "Moisture S1: " / percent1 / "%"/ " Irrigaion sistem OFF" or "Moisture S1: " / percent1 / "%"/ " Irrigaion sistem ON" Thanks a lot!
  6. Spark gap transmitter, is my guess. Very old school RF tech... we are talking Marconi-age stuff... UPDATE: I would be extremely careful applying any power to it.... looks like those coils would put the voltage up in the 10's of KV, easily.
  7. Does anyone have any idea what this might have been used for?
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  9. Hello everyone, Realtek's RTL8722DM development board is now supported in the Linux and macOS operating systems. You can now program and flash the RTL8722DM in all three operating systems, using either the Arduino IDE or the SDK with GCC. The RTL8722DM is an IoT-ready MCU powered by an ARM Cortex-M4 core at up to 200MHz coupled with a Cortex-M0 core at up to 20MHz. It includes support for standard MCU features such as UART / I2C / SPI / ADC / PWM / GPIO interfaces, as well as dual band WiFi connections at both 2.4 GHz and 5 GHz, and BLE 5.0 connections. More information on RTL8722DM capabilities can be found at: https://www.amebaiot.com/en/amebad/ Join in the community discussions at: https://www.facebook.com/groups/AmebaIoT/ https://forum.amebaiot.com/ Purchase links for the various Realtek development boards can be found at: https://www.amebaiot.com/en/where-to-buy-link/
  10. I just came across a post from you dated 2006 where you linked to tons of ebooks about PICs and microcontrollers. All those links are gone,and now I search on the "usual venues" and come up with tons of ebooks for RasPi and Arduino, I already have those. Most I purchased them myself on HumbleBundle. but I can find none of these classics from a decade or two ago. I'm specially interested in the ones related to PICBASIC. Got any hints of where to look for them? Maybe a RAR megapack uploaded somewhere? or a torrent? You're my last hope... TIA

  11. Hi Edy, I have this service manual ,the DX110 when I took some seminar in sharp. let me know if you still need it. so i could up load it.
  12. References Article: https://www.pcbway.com/blog/technology/4000W_Standalone_Digital_AC_Dimmer_Using_STM32.html [1]: TLP521 Datasheet: https://www.futurlec.com/Datasheet/LED/TLP521.pdf [2]: BTA26 Datasheet: https://www.mouser.com/datasheet/2/389/cd00002264-1795706.pdf [3]: AN437, ST Application Note: https://www.st.com/resource/en/application_note/cd00004096-rc-snubber-circuit-design-for-triacs-stmicroelectronics.pdf [4]: MOC3021 Datasheet: http://www.farnell.com/datasheets/97984.pdf [5]: AMS1117-3.3 Datasheet: http://www.advanced-monolithic.com/pdf/ds1117.pdf [6]: STM32F030F4 Datasheet: https://www.mouser.com/datasheet/2/389/dm00088500-1797910.pdf [7]: Schematic Symbol and PCB Footprint of TLP521: https://componentsearchengine.com/part/1774908/model/download [8]: Schematic Symbol and PCB Footprint of MOC3021: https://componentsearchengine.com/part/229006098/model/download [9]: Schematic Symbol and PCB Footprint of BTA26-600: https://componentsearchengine.com/part/1587919/model/download [10]: Schematic Symbol and PCB Footprint of AMS1117-3.3: https://componentsearchengine.com/part/656857/model/download [11]: Schematic Symbol and PCB Footprint of STM32F030F4: https://componentsearchengine.com/part/182014793/model/download [12]: Electronic CAD Plugins: https://www.samacsys.com/library-loader-help [13]: 2N7002 Datasheet: https://www.diodes.com/assets/Datasheets/ds11303.pdf [14]: Schematic Symbol and PCB Footprint of 2N7002: https://componentsearchengine.com/part/228320879/model/download
  13. Realtek's ameba dev. board is capable of USB OTG and SDIO thus making it possible to take photo with a UVC camera and store it in a SD card via SDIO. Here, combining these 2 function, one can easily create a Time Lapse Photography with merely an arduino size MCU. Here is a tutorial about it, Preparation Ameba x 1 SD card or MicroSD card x 1 SD sniffer x 1 (optional) Logitech C170 web cam x 1 Micro USB OTG adapter x 1 Example In this example, we use UVC to take photos and save to SD card at regular time, which is similar to time lapse photography. Open the sample code in "File" -> "Examples" -> "AmebaSdFatFs" -> "time_lapse_photography" In the sample code, we start the UVC at first, then initialize SD FAT FS. In loop(), use UVC to capture photo every three seconds, and the captured photos are numbered in 0001.jpeg, 0002.jpeg, 0003.jpeg, ... There are some tools to turn these photos to a video. We use ffmpeg here: https://ffmpeg.org/ In Windows OS environment, type the command in the directory of all UVC photos: ffmpeg -framerate 30 -i %04d.jpeg -vf fps=30 -pix_fmt yuv420p output.mp4 The explanation of the arguments in the command: -framrate: By specifying this argument, you tell ffmpeg to use the time handled by framerate to be the timeline. Here we use 30, which means in 30 photos are displayed per second. -i: use this argument to specify input file name. We use "%04d.jpeg" to tell ffmpeg to read the files from 0000.jpeg, 0001.jpeg, 0002.jpeg, ... fps: the framerate of output video, we use 30 frames per second here. The last argument is the output file name. Demo video: Code reference The sample code is comprised of two parts: use UVC to capture photo, and write file to SD card. The UVC part please refer to previous "UVC – Use UVC To Send Image" example. And SD part please refer tp the "SDIO – Edit Files In SD Card" example
  14. Hi, Guy I have joined this forum some time. Recently, i have just finished a project development. The project is building CMD line(cli) tools for multiple OS, windows10, linux and macos. I just want to share you guys my experience with the 3 platform. BTW, the RTL8722DM dev from following link is what my project is used for. https://www.amebaiot.com/en/amebad-arduino-getting-started/ Basically, windows is the most convenient platform. It has all kind of tools for compiling c, cpp and c# projects. One things need to be considered. 1, if you use visual studio for c# in windows. the tool you have build is not easy to transfer in to the other platforms. To support a visual studio c# project there a lot of works to do in linux and macos. Additionally, you have to set up the toolchain/compiler properly for windows. Linux has no issue to compile my project. But lack of development tools and "sudo" sometimes gives you big problem. For, c and cpp development, i suggest that linux is the best and all project is able to transfer to the other platform. Macos has the most limitations. i am a windows person so using macos to development is a bit trouble for me. And the disc name of macos always has a "space" which is very bad for process command. However, i would say the project made by macos is the most stable and small size one. To summarize, if you trying to make a multiple platform/OS support project. I would recommend to use c/cpp project and start on linux. Please try not to start with windows, windows is the easiest way, but will gives you troubles when trying to support all 3 platform/OS.
  15. Most mainstream Android and iOS smartphones now include support for NFC functionalities. NFC is a non-contact protocol that makes it easy to transmit and receive small packets of data wirelessly. Furthermore, it also allows for passive devices, which need no battery and receives all the energy required to operate from a NFC reader such as a smartphone or card reader. Realtek's RTL8195AM development board includes a NFC antenna for use with the integrated NFC driver in the RTL8195AM chip. This opens up a new way for applications to interact with users through contactless NFC transactions. Examples would be to use NFC to sign in and out of a service, or to use NFC to open a web page on a smartphone. For more information on RTL8195AM NFC capabilities, refer to the NFC example guide: https://www.amebaiot.com/en/ameba-arduino-nfc-open-web/ Join in the community discussions at: https://www.facebook.com/groups/AmebaIoT/ https://www.amebaiot.com/en/ Purchase links for the various Realtek development boards can be found at: https://www.amebaiot.com/en/where-to-buy-link/
  16. "Could a capacitor smooth the frequency? " If one does not know what is wrong with the system then one can not know what the affects of a capacitor would be. you have a 12 5kw diesel generator the generator outputs 120 or 240 volts at 50 or 60 hertz. the generator supplies the mains that has numerous outlets on the boat. the generator output is stable until you turn on the ac unit. with the ac running the voltage at the various outputs are no longer 50 or 60 hertz but varying in frequency 6: adding any load to an output corrects the problem. Is that correct?
  17. LoRa is a low-power wide-area network protocol developed by Semtech. It has a typical range of 10KM at low power consumption which is ideal in some IoT applicaitons. Using LoRa on Realtek's Ameba Dev. board is very easy, here is a tutorial about it, Materials Ameba x 1 Dragino LoRa Shield x 2 Example Dragino Lora Shield is a long range transceiver and based on Open source library. It allows the user to send data and reach extremely long ranges at low data-rates.It provides ultra-long range spread spectrum communication and high interference immunity whilst minimising current consumption. Due to different frequency regulations on each country, please notice the frquency LoRa Shield used when you purchase it. Download the LoRa Library: https://github.com/ambiot/amb1_arduino/raw/master/Arduino_libraries/AmebaLoRa.zip Refer to the documentation on Arduino website to install library and add the .zip file to Ameba: https://www.arduino.cc/en/Guide/Libraries#toc4 Dragino LoRa Shield SPI example wiring explanation: Dragino LoRa Shield can be embedded on Ameba board directly, but the Ameba CS pin is different to the standard SPI protocol. Therefore, Dragino LoRa Shield CS pin cannot connect to Ameba CS pin directly. Modify and pull the CS pin which is pin 10 toward inside and connect to pin 0 with dupont line on Dragino LoRa Shield. The example is shown below: Dragino LoRa Shield SPI Data is produced from ICSP SPI BUS, then connect to AMEBA SPI pin as follows: Below is the RTL8710 Wiring Diagram: Example Illustration This example uses send and receive code to do the functional verification for two Dragino LoRa Shield. One is for sender and another one is fr receiver. Open “File” -> “Examples” -> “AmebaLoRa” -> “LoRaSender” and LoRaReceiverCallback. Compile them separately and upload to Ameba, push the Reset button. Then you can see the results on the terminal:
  18. Yes, that is true, that is how it works. But, the live frequency is steady until that inverter controlled compressor is on. All other loads don't effect the frequency. The compressor has such a effect on the frequency, that fans nearly stop one moment, and look like a airplane propeller the next!!! All the while, the generators rpm is stable! Any resistive load thats,applied, steady the frequency even when the compressor is running! I can't have a hair dryer running 24/7 just to stabilize the frequency! Could a capacitor smooth the frequency? I can't have a hair dryer running 24/7 just to stabilize the frequency! Could a capacitor smooth the frequency? This is on a boat, why does the variable frequency affect the rest of the AC? The compressor doesn't like it either, it eventually shuts down on error. Again, aNY load added smoothes out the frequency and then everything is fine.
  19. 48 volts is above the absolute voltage for this voltage regulator: 35 volts maximum:
  20. In that type of air conditioner the input ac voltage is converted into dc via a power supply. The dc voltage is converted (inverted) into variable frequency ac. The frequency depends on the demand on the unit. A microcontroller samples the ambient air temperature and adjusts the speed of the compressor motor via the frequency of the ac applied to the compressor motor. Invert versus convert is interesting: Inverter - dc to ac converter - ac to ac (transformer, etc) converter - dc to dc (potentiometer, etc) power supply - ac to dc
  21. I have a problem using lm7812 it produced output voltage I connected 48v battery as input voltage but this 12v output didn’t carry just dc fan please what’s the solution to this problem but I remember I do not filter this terminals
  22. I have severe frequency fluctuations when using a inverter controlled airconditioner. The frequency is stable with any other load or lack of load. The power supply is a 12 5kw diesel generator which is more than adequate. Any resistive load smooths out the frequency perfectly. Unstable frequency is only seen when airconditioner is on. The RPM is,stable The fluctuations are HUGE 3-112 Hz! Can a capacitor remedy this?
  23. see: http://starseedsportal.org/tag/stephen-dickens-magnesium-water-copper-battery/ plus other sites; search on "stephen dickens water battery" Also see Voltaic pile at: https://en.wikipedia.org/wiki/Voltaic_pile
  24. Got a water powered motor on my live cam. Built these types of systems many years ago. Got the PDF on such as well. You can view the live cam of the water powered motor at http://watermotor.ddns.net/
  25. Dave, Can you provide a sketch showing the transistor layout between U1 and U3, as well as your modified the power supply to U1?
  26. Robotics will be one of the greatest job creators in contemporary history. But are there enough people eligible to fill those jobs? As different sectors announce skill shortages, we have been looking at how robotics are affected and which skills are the most important to employers. automated solutions
  27. Realtek's Ameba dev board comes with USB OTG function as well as video processing power, combined with its WiFi capabiilty, it can live stream video to your PC or smartphone, here is a tutorial about it. Preparation Ameba x 1 Logitech C170 web cam x 1 Micro USB OTG adapter x 1 Example There are 3 micro usb host on Ameba, the one at the back supports OTG UVC, by which the USB camera can transmit video data to Ameba, and Ameba converts the video to rtsp streaming and sends it to the network. We use Logitech C170 webcam in this example, please find its detailed spec in the link below: http://www.logitech.com/en-in/product/webcam-c170 The default video streaming format of Ameba is Motion JPEG 320 x 240, users can adjust the parameters according to the need. Detailed wiring is as below. Connect Micro USB OTG to Ameba, then connect the USB camera. Note that in the above wiring diagram, the webcam uses Ameba as power source. If the power supply of Ameba is not sufficient, this would cause the camera unable to work. That is, you have to make sure the power source provides sufficient power to Ameba, or you have to choose the USB OTG which can be connected to external power source. Next, open the example in "File" -> "Examples" -> "AmebaUVC" -> "uvc_basic" In the sample code, please fill in the SSID and password of the network you want to connect with. Then upload it to Ameba, and press reset. Then open the Serial Monitor: You can see that we are using the default MJPG (Motion JPEG) with resolution 320 * 240 and frame rate 30. After the settings are done, the log message prints the link for the streaming: rtsp://192.168.1.70/test.sdp Next, we use video player supports video streaming, e.g., VLC Player - http://www.videolan.org/vlc/ Open VLC player, click "Media" -> "Open Network Stream" Fill in the link of the streaming, (Please make sure the computer and Ameba are connected to the same wireless AP) VLC also provides application for smartphone: Click "Stream" Enter the link, and make sure the smartphone and Ameba are connected to the same network.
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