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Fused crystal oscillator
What do we mean by fuse bits and fused crystal oscillator? Don't mind but, because of Electrical Engineering, had Eletronics in syllabus but don't have that much background idea, these words are somewhat new to me. How a simple writing operation of fuse bits will cause a huge damage to the Microcontroller, we are simply configuring them to some other value than the defined value.

Also you said in precaution section that, we should remove all the external connections with mainboard except USBASP programmer while flashing into the memory of Microcontroller from the PC. But, doesn't the given supply of SMPS to the mainboard may contribute to a damage to the microcontroller.

OpenPLC-with-LDmicro Programming-OpenPLC 05-06 min 50-60 sec 01-06-22, 2:12 p.m. sc256356


We expect the participants to have basic knowledge of electronics, micro controllers, Control systems and Ladder Logic to follow this series. There are lot of theory and how to use fuse bits is available on internet, that you have to search it.

Please have a look at:,represents%20a%20different%20fuse%20setting

Fuse bits instructions are for the person who will manufacture the PCB and make his own OpenPLC.
We instructed to take out USBASP programmer from the board, because the power provided by the PC USB port is not sufficient to drive experiment.
If the main board is powered from both PC USB and Power supply, it may give issues to main board or PC. This are all Caution instructions.

01-06-22, 4:14 p.m. NirmalaVenkat

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