What is RESET condition?
RESET is a condition where the device starts operating from a unknown condition. Known condition meant the registers shall be intialized to a default state. We see that the registers mention it as POR state.
POWER-ON RESET (POR):
Power ON Reset occurs during the circuit power ON. If the power is below a pre-defined threshold, the Microcontroller remains in RESET condition.
JTAG RESET:
JTAG RESET is from a external debugger. So, you can reset your device using the external GUI interface which we call the IDE.
SOFTWARE RESET:
Software RESET helps RESET your device through software instruction.
BROWNOUT RESET:
BROWNOUT is a condition which occurs when the power drops below a certain threshold. Microcontrollers monitor the power supply input to them and brown out condition occurs based on the power rail.
EXTERNAL RESET:
This is the RESET applied through a microcontroller pin. Generally, we provide a delay on this pin using an external R-C circuit. This delay is to ensure that microcontrolle comes to a stable state before starting the instruction execution.
WATCHDOG TIMER:
Any erratic behaviour behaviour by the firmware inside the microcontroller can be receovered using the Watchdog timer. The watchdog timer must be regularly reset to ensure that unintentional RESET doesn't happen.
1. Ultimately, all the above reset types merge to a SYSTEM RESET signal.
2. We have to remember that, if the PCB design is not proper, any noise can get induced on the device and untimtentional RESET can occur leading to product malfunction.
3. All these RESET signals status shall be part of a register with bit assigned to each type of RESET.
4. once the RESET occurs, the instruction jumps to RESET handling routine.
5. Some Microcontrollers have RESET options for illegal opcode generation, improper register configuration.
RESET is a condition where the device starts operating from a unknown condition. Known condition meant the registers shall be intialized to a default state. We see that the registers mention it as POR state.
POWER-ON RESET (POR):
Power ON Reset occurs during the circuit power ON. If the power is below a pre-defined threshold, the Microcontroller remains in RESET condition.
JTAG RESET:
JTAG RESET is from a external debugger. So, you can reset your device using the external GUI interface which we call the IDE.
SOFTWARE RESET:
Software RESET helps RESET your device through software instruction.
BROWNOUT RESET:
BROWNOUT is a condition which occurs when the power drops below a certain threshold. Microcontrollers monitor the power supply input to them and brown out condition occurs based on the power rail.
EXTERNAL RESET:
This is the RESET applied through a microcontroller pin. Generally, we provide a delay on this pin using an external R-C circuit. This delay is to ensure that microcontrolle comes to a stable state before starting the instruction execution.
WATCHDOG TIMER:
Any erratic behaviour behaviour by the firmware inside the microcontroller can be receovered using the Watchdog timer. The watchdog timer must be regularly reset to ensure that unintentional RESET doesn't happen.
1. Ultimately, all the above reset types merge to a SYSTEM RESET signal.
2. We have to remember that, if the PCB design is not proper, any noise can get induced on the device and untimtentional RESET can occur leading to product malfunction.
3. All these RESET signals status shall be part of a register with bit assigned to each type of RESET.
4. once the RESET occurs, the instruction jumps to RESET handling routine.
5. Some Microcontrollers have RESET options for illegal opcode generation, improper register configuration.
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