Specification Sheet

Processor Configuration Register Definitions and Address Ranges
36 Datasheet, Volume 2 of 2
2.5 Main Memory Address Range (1 MB – TOLUD)
This address range extends from 1 MB to the top of Low Usable physical memory that is
permitted to be accessible by the processor (as programmed in the TOLUD register).
The processor will route all addresses within this range to the DRAM unless it falls into
the optional TSEG, optional ISA Hole, or optional Processor Graphics stolen VGA
memory.
This address range is divided into two sub-ranges:
• 1 MB to TSEGMB
• TSEGMB to TOULUD
TSEGMB indicates the TSEG Memory Base address.
Figure 2-5. Main Memory Address Range