Microcontroller utilizing internal and external memory

摘要

A circuit for selecting a base memory to be accessed by a microcontroller in response to a command from the microcontroller. An input receives the command from the microcontroller. The command selectively instructs the circuit to reset the microcontroller and signal the microcontroller to access an internal memory as the base memory. Also, the command selectively instructs the circuit to reset the microcontroller and signal the microcontroller to access an external memory as the base memory. A reset output is used to send the reset signal to the microcontroller, and a memory select output is used to send a memory select signal to the microcontroller. A logic circuit processes the command received from the microcontroller, and selectively sends an internal base memory select signal on the memory select output in response to the command received from the microcontroller, while the reset signal is being processed by the microcontroller, and selectively sends an external base memory select signal on the memory select output in response to the command received from the microcontroller while the reset signal is being processed by the microcontroller.