The S3C821A is a microcontroller with a 48-Kbyte mask-programmable ROM embedded. The S3P821A is a microcontroller with a 48-Kbyte one-time-programmable ROM embedded. Using a proven modular design approach, Samsung engineers have successfully developed the S3C821A/P821A by integrating the following peripheral modules with the powerful SAM8 core: -- Six programmable I/O ports, including five 8-bit