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  P10 Led Panel 32x16 consist of 512 leds. There are  2 connectors, called  Hub1.2  (8x12 male header) and 5v power connector. Hub1.2 placed left side of the board shown in image below is input, right one is the connector to connect another p10 panels input. Pin definition of Hub1.2  is shown in image.  ENABLE pin  is the pin which allows you to control the panel is working state or stop state. Panel enables when it is driven a HIGH signal, When it is driven low it does not matter another pin states, panel stops working. A, B are row selectors, this pins represent a 2 bit binary number allow you to select one of four rows in a sequence. Selecting a row means that, the leds on the selected row are powering their anod pins. There are 16 rows in total(A1-A16), and they are in a group of 4. Each group of rows are represented with the same color in the images below. Look at the table, driving A and B with a LOW signal means selecting rows labelled A1,A5,...

 Programming Bluepill via Stm32f4-discovery      If you have that handsome guy : bluepill and do not have stlink programmer, also you have a discovery board, "What a low probability for this article to be read." -but ok, I am the one, faced with this situation maybe some other one also can be. 😁 Step1 : Removing St-Link Jumpers      There are two jumpers on area labelled CN4, (marked in purple square) if they are jumped like on the picture, this means embedded st-link programmer can program discovery board, if you remove them, st-link programmer connection to discovery MCU is removed and free to use externally. Step2 : Connecting St-Link Pins to BluePill There are six pins on the area called CN4, marked in the picture. The pin numbers starting 1 from top and go down to 6. We just use 1 to 4 pins. If you want to reset your bluepill via button on the discovery board you can connect NRST to Reset pin of Bluepill. Anyway, the pins of bluepill : B...

 Let's code! Expalantions are in the code area. Happy Coding! /* * DHT 11 driving without library * * http://en.devrelerim.com * Author : Hakan OZMEN (hakkanr@gmail.com) * Date : 30.03.2021 * * You can change or share all / or same part of * this code. Free of charge! :) */ uint8_t data [ 5 ] ; // to save our 8bit * 5 data void setup ( ) { Serial . begin ( 115200 ) ; } /* *  This function count an 8bit integer value *  while given signal is not changed *  no need to measure time counting is also *  need time ;) */ uint8_t expectedSignal ( bool level ) {   uint8_t count = 0 ;   while ( digitalRead ( 2 ) == level ) count ++ ;   return count ; } void loop ( ) { delay ( 2000 ) ; // wait 2 secs for sensor to initialize Serial . println ( "----------------------" ) ; pinMode ( 2 , INPUT_PULLUP ) ; // Standard is HIGH delay ( 1000 ) ; pinMode ( 2 , OUTPUT ) ; // make pin 2 output...

 What's inside DHT11 sensor , I've removed the plastic case and what I saw is :     There is a resistive type humidity measurement component, a NTC to measure temperature and a 8 bit microcontroller and it uses single-wire serial interface to communicate  with other systems. Measurement range 0-50 °C in temp and 20-90%RH in humidity. Accuracy for temp is ±2°C, ±5%RH for humidity, and last information about it is resolution is 1.          What about the power? it can work between 3v and 5.5V, this means you can use it 3.3v boards and also 5v boards. Communication Process      This is the part I like the most !     - One communication process is about 4ms.     - Data format : 8bit Humidity (integer part) 8bit Humidity (decimal Part) 8bit Temp (integer part) 8bit Temp (decimal Part) 8bit checksum totally we have 40 bits of data to deal with. Let's look at the signal on data pin with logic analyzer ...

     In this article, we are looking for how DHT series sensors work and how can we drive them without using any library. Especially about DHT11 sensor here in this content. DHT 11 is a very cheap way to measure temperature and humidty in embedded systems, like arduino or STM based development cards      You can see two types of DHT11 sensor which one have 3 pins with a board, another is just sensor. Difference between two is just a pullup resistor, If you have alone one, you should put a 10K resistor, signal pin to VCC pin to made them the same, there is no any difference except alone one has an unsused pin !?     This Sensor can be used with Adafruit's DHT sensor library , with a requirement which is Adafruit's Unified Sensor Library. You can find them Library Manager on Arduino IDE . It's very easy! Just click Tools * Manage Libaries, you will face with Library manages which has a text box Fill your search... written.  Text there DHT Sen...

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