MICROWIRE/PLUS Application
Figure 25 illustrates a MICROWIRE/PLUS arrangement for an automotive application. The microcontroller-based sys- tem could be used to interface to an instrument cluster and various parts of the automobile. The diagram shows two HPC167064 microcontrollers interconnected to other MICROWIRE peripherals. HPC167064 1 is set up as the master and initiates all data transfers. HPC167064 2 is set up as a slave answering to the master.
The master microcontroller interfaces the operator with the system and could also manage the instrument cluster in an automotive application. Information is visually presented to the operator by means of a LCD display controlled by the COP472 display driver. The data to be displayed is sent serially to the COP472 over the MICROWIRE/PLUS link. Data such as accumulated mileage could be stored and re- trieved from the EEPROM COP494. The slave HPC167064 could be used as a fuel injection processor and generate timing signals required to operate the fuel valves. The mas- ter processor could be used to periodically send updated values to the slave via the MICROWIRE/PLUS link. To speed up the response, chip select logic is implemented by connecting an output from the master to the external inter- rupt input on the slave.
TL/DD/11046 – 32
FIGURE 24. MICROWIRE/PLUS
TL/DD/11046 – 33
FIGURE 25. MICROWIRE/PLUS Application
22
