National Instruments HPC167064 - Manual (Page 22)

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