If an investment has already been made in masked-ROM devices, it is costly to throw them away. It allows customers to quickly program a new version of the code to respond to software updates immediately. They can be programmed individually so that product serial numbers can be embelied. OTP microcontrollers offer increased flexibility and faster time to market. They can also meet low volume application needs that are under the minimum masked-ROM requirements.
Flexibility offers value that is often more important than the actual microcontroller cost.
This two-wire serial bus is a simple yet very powerful means of connecting microcontrollers and their peripheral devices together. It takes very little board space since the bus interface is on-chip. And, it takes very little chip space, since it uses only two pins, serial data and serial clock. Yet, it is a powerful bus that supports multimaster operation to allow any number of controller devices to be connected to the bus at the same time. Its operational protocol directs traffic and maintains a smooth data transfer between all devices connected to the bus.