Motorola MVME172 15. MK48T58 BBRAM/TOD Clock Memory Map, Address Range Description Size Bytes

1

Board Description and Memory Maps

BBRAM/TOD Clock Memory Map

The MK48T58 BBRAM (also called Non-Volatile RAM or NVRAM) is divided into six areas as shown in Table 1-15. The first five areas are defined by software, while the sixth area, the time-of-day (TOD) clock, is defined by the chip hardware. The first area is reserved for user data. The second area is used by Motorola networking software. The third area may be used by an operating system. The fourth area is used by the MVME172 board debugger (MVME172Bug). The fifth area, detailed in Table 1-16, is the configuration area. The sixth area, the TOD clock, detailed in Table 1-17, is defined by the chip hardware.

Table 1-15. MK48T58 BBRAM/TOD Clock Memory Map

Address Range	Description	Size (Bytes)
$FFFC0000 - $FFFC0FFF	User Area	4096
$FFFC1000 - $FFFC10FF	Networking Area	256
$FFFC1100 - $FFFC16F7	Operating System Area	1528
$FFFC16F8 - $FFFC1EF7	Debugger Area	2048
$FFFC1EF8 - $FFFC1FF7	Configuration Area	256
$FFFC1FF8 - $FFFC1FFF	TOD Clock	8

1-40 Computer Group Literature Center Web Site