Understanding Smart Sensors - Nomads.usp

Using MCUs/DSPs to Increase Sensor IQ 113MCUtargetsystemcircuitryEEPROMMCUprogrammerTerminalControlMCUI/OportBustransceiverMCU(MC68HC05)andcontrolcircuitsUserpseudoROMMonitorRAM/ROMTerminaland hostI/O port(DACIA)Tx0Rx0ControlHostcomputerTx0Rx0ControlFigure 5.10 MC68HC05EVM development tool for 68HC05 MCU.interfaced to a host computer such as an IBM-compatible PC or Apple Macintosh® [16]. All the essential MCU timing and I/O circuitry already exist on theEVM to initiate the development process. MCU code can be generated using aresident one-line assembler/disassembler or downloaded to the user programRAM through the host or terminal port connectors. The code can be executedby several debugging commands in the monitor.Freeware obtained through the World Wide Web can be used in softwaredevelopment. Information, development tools, and documentation establishedover several years of customer usage are available for many MCUs. As a result,the capability exists to develop the smartest sensor that can be defined today.5.7 Sensor IntegrationThe fourth level in advancing integration (see Figure 1.7) is to migrate thedeveloped MOS interface onto the MCU. The basic sensor element is interconnectedin close proximity to the enhanced MCU in the same package. Nowthe sensor itself is the only element that does not need to be MOS processcompatible. The fourth level is also the optimum point at which to consider