![]() The function will fill-in 32 bytes of the bufferINFO memory with the information in ANSI text format. To obtain the information about the status of the user application we call the operating system functionĪppInfo(). Since the dit() and dah() functions are written to insert a pause lasting one dot after every beep, we need to add a pause with two dots length to finish the character. Then, if the result of masking is 1 we broadcast dash, otherwise it is dot. Storing the whole code in an array sorted alphabetically is very natural and helps in picking the code for a given character. The central part of the byte “1010” is the code and the extra leftmost 0 is one bit we did not use. The last 3 digits 100 (decimal value 4) tell us that the code for C has 4 beeps. For example the letter C would be 0b0.1010.100. We decided to store the length in rightmost bits. Since the length is no more than 5 beeps, there are 3 bits left to store the length of the code in the same byte where we store the code. The length of the Morse code for individual characters varies. The syntax allows for a “.” (period) symbols to separate individual bits for readability purposes. Fortunately, the Knudsen’s C is extended to support binary literals that you can write as bin(xxxxxx) or 0bxxxxxx where the x is either 0 or 1. ![]() For example the letter C (dah-di-dah-dit) would be encoded as 1010 or 0xA in hexadecimal. ![]() The Morse code being made of dots and dashes only naturally suggests binary storage with 1 for a dash and 0 for a dot. Therefore, we need to plan to store the Morse code in the memory efficiently. There is not much RAM to waste on tiny PIC chips. Two macros to conveniently handle timing: The transceiver timer goes in 10ms intervals. The dot for faster transmissions known as CODEX should last 50ms, for slower transmissions known as PARIS 60ms. The pause between words should last as 7 dots. Three times longer than the dot and there is a pause lasting the same time as one dot between beeps in the character and a pause lasting as one dash between characters. The Morse code consists of dots (short beeps called dits) and dashes (longer beeps called dahs). Our program should run well on any IQRF smart transceiver and principles shown here are applicable to a wide range of PIC microcontrollers. We will use TR-52BA transceiver that is equipped with PIC 16F688 microcontroller. The IQRF transceiver is equipped with a built-in PIC microcontroller that we want to program. We do not really care about the radio connectivity in this project. The RF transceiver is radio transmitter and receiver built into one. IQRF is a complete modular platform for wireless connectivity based on smart transceivers that are affordable and very easy to use. We will use the Morse code to broadcast information about the current status of the TR-52BA board and application installed. ![]() Morse and Alfred Veil to transfer textual information as a series of on/off tones, lights or clicks that can be directly understood by a skilled listener or observer. The Morse code was developed 176 years ago by Samuel F. The program is written in C and compiled by free CC5X C Compiler for the PICmicro Devices version 3.4 from B. We will see how Morse code can be used for communication from a tiny IQRF (see reference ) TR-52BA board that contains an LED and a PIC16F886 microprocessor. ![]()
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