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--- embedded:c [2025/09/11 14:44] – [VARIABLES] v1ctor
+++ embedded:c [2026/03/06 13:16] (current) – [VARIABLES] v1ctor
@@ Line 49: / Line 49: @@
   printf("%c\n", a2); // prints also 'A'
 </code>
+==== PRINTF FORMATTERS ====
+  * %u - unsigned
+  * %lf - double
+  * %f - float
+  * %le, %e - real number in the scientific representation
+  * %#x - hexadecimal with a leading 0x
+  * %s - string
+==== ASCII ==
+<code c>
+char a1 = 'A'; // Compiler will replace 'A' with 65
+</code>
+If an arithmetic operator has one floating-point operand and one integer operand, however, the integer will be converted to floating point before the operation is done.
+==== PRECEDENCE ====
+  - !=
+  - =
+==== LOGICAL OPERATORS ====
+  * && - AND
+  * || - OR
+  * ! - NOT
+**True** is anything but 0, e.g.
+<code c>
+uint8_t a = 4;
+uint8_t b = 8;
+uint8_t c = 0;
+c = a && b; // c == 1
+</code>
+==== BITWISE OPERATORS ====
+  * & - bitwise AND (usually used to test or clear bits)
+  * | - bitwise OR (usually used to set bits)
+  * ~ - bitwise NOT (unary operator, usually used to clear bits)
+  * ^ - XOR (usually used to toggle bits)
+<code c>
+a = ~c; // bitwise unary NOT
+</code>
+==== BITWISE SHIFT ===
+  * >> - a value will be divided by 2 for each right shift
+  * << - a value will be multiplied by 2 for each left shift
+Example clearing the 4th bit with a bitwise shift operator and negation:
+<code c>
+data = data &~(1<<4);
+</code>
+Example bit extraction for bits [14:9]. The algorithm:
+  - Shift the portion to the right, until it touches the LSB
+  - Mask the value to extract only 6 bits [5:0]
+<code c>
+data = data >> 9;
+data &=63;
+</code>
+==== LOOPING ====
+WHILE
+<code c>
+while(expression) // repeat execution of code inside the loop body until expression evaluates to 0
+{
+    statemen1;
+}
+</code>