Imagine a temperature monitoring device that reads sensor values every second. Initially, the device works correctly. After running for several hours, the displayed temperature suddenly becomes incorrect. The sensor is working. The hardware connections are correct. The program is still running. So, what went wrong? One possible reason is an integer overflow problem inside the firmware. Integer overflow is a common programming risk in embedded applications because firmware frequently processes sensor values, counters, timers, communication packets, and memory sizes. A small calculation error can produce an incorrect result without immediately stopping the program. Detecting signed and unsigned integer overflow in firmware is therefore an important skill for Embedded C developers. This article explains how to identify overflow, write safer arithmetic operations, use compiler tools, and test firmware under different conditions. What Is Integer Overflow Detection? Integer overflow detect...
Endianness breaks communication when one system sends multi-byte data in one byte order and another system reads the same bytes using a different byte order. For example, one device may send: 12 34 meaning: 0x1234 But another device may interpret those same bytes as: 0x3412 The bytes are identical. The interpretation is different. This can cause wrong sensor readings, invalid commands, communication failures, and difficult embedded system firmware bugs. The Main Problem: Same Bytes, Different Meaning Imagine two embedded devices. Device A → Communication Data → Device B Device A sends: 12 34 Now Device B must know exactly what those bytes mean. Are they: 0x1234 or: 0x3412 The answer depends on the communication protocol. If the protocol is not followed correctly, Device B may calculate the wrong value. That is how endianness can break communication. A Simple Example Suppose Device A wants to send the number: 0x1234 If the communication format uses big-end...