User’s Manual
M68HC12A4EVB Evaluation Board — Rev. 1
86
Hardware Reference
MOTOROLA
Hardware Reference
4.7 Memory
The EVB’s memory is discussed here.
4.7.1 Memory Types and Sockets
The EVB has footprints for two SRAM sockets (U4 and U6A) and two ROM
sockets (U7 and U9A). The ROM sockets hold memory for D-Bug12, the EVB
operating firmware, or for user programs. The SRAM sockets hold memory for
user data or programs. The 8-bit memory arrangement allows MCU operation
in both single-byte and double-byte modes. The RAM and ROM footprints
support different memory device types (SRAM, EPROM, and EEPROM) and
sizes (28- and 32-pin, 8 to 512 Kbytes, 300- or 600-mil spacing).
Figure 4-1
shows how the external memory sockets are used.
Table 3-5. Factory-Configuration Memory Map
depicts the EVB’s default
memory usage. Note that the map is valid only for the factory-supplied memory
configuration.
NOTE:
The user-available area in factory-supplied EPROM requires that the ROM
chips be reprogrammed with the custom code. For more information, refer to
Appendix E. Customizing the EPROMs
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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