But after several weeks of research, the designer's elation changes to frustration as the black box is cracked open and with it comes the realization that the resources required to implement connectivity leaves very little for the actual application. Connectivity heavily taxes the critical core resources of any processor or microcontroller, requiring larger program memory, larger data memory and faster operating frequency. Microcontroller manufacturers have been monitoring the connectivity market and have started to design 8-bit versions with more memory and higher operating frequencies to facilitate the application as well as the connectivity.
Connectivity encompasses two aspects of a design.
The first is the medium over which messages are transferred. Wired connectivity includes Ethernet, telephone and power line. Wireless includes standard RF transmission, spread spectrum and cellular. The largest growing market for embedded connectivity is for residential use. While in some cases the microcontroller is not directly involved with the hardware to transmit and receive messages over the medium, it must be able to keep up.