4-3. Application Notes
U3-1021
4-8
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Westinghouse Proprietary Class 2C
8. Figure 4-5 provides a memory map for the 80C186EC processor. Note the
following points:
— The 640 Kbytes DRAM (addresses 00000H - 9FFFFH) are available for use
by the DOS operating system and DOS application programs.
— For purposes of communication with the Controller, store data in the dual
port RAM.
— The remaining memory addresses are reserved for Westinghouse use.
9. Specific I/O addresses are available to the user application to write to the eight
status LEDs (1 - 8), and read or write to the J2 Applications serial port. Table 4-
1 describes the I/O addresses which may be accessed by the user application.
All other I/O addresses are reserved for Westinghouse use.
10. The LC incorporates a watchdog timer which can be used by the application, if
desired. The timer will time-out after 160 msec, unless the application program
writes any byte value to I/O address 0900H.
11. When using the LC module, the watchdog status is available to the Controller
through the SLCSTATUS algorithm. If the watchdog timer feature is not
implemented in the user’s application, the applicable status bit will always
equal 0.
If an LC watchdog time-out is detected, the LC can be reset by removing the LC
module from its Base Unit, waiting five seconds, and then replacing the module.
12. After the LC is reset, the Ovation IO Bus registers (dual port RAM) are
uninitialized. The application program in the LC should initialize these memory
locations, as necessary.
