Toshiba TOPAS900 user manual Normal Operation Mode, Memory MAP

Users Manual TOPAS900 Flash V2.1

000000H

0000A0H

0020A0H

MEMORY MAP

Boot Memory : Boot ROM Reset-Conditions :

/EA = H

/BOOT = L (single boot mode)

Internal I/O (160 bytes)

Internal RAM (8K bytes)

external memory

external memory

010000H

04FFFFH

RAMSTART*

ROMSTART*

FFF800H

FFFFFFH

Internal Flash ROM (256K bytes)

External RAM (128 K bytes)

External Flash Memory (512 K bytes)

Internal Boot ROM

*ROMSTART is programmed by CS2 registers

*RAMSTART is programmed by CS1 registers

Figure 12 : Map for Internal Flash Programming

5.1.4. Normal Operation Mode

For normal operation the /BOOT line is switched to High which disables the Boot-ROM. In this mode there are two possibilities for mapping the internal flash memory determined by the /EA (external address) line. The TOPAS900 Flash board has external flash memory for the ROM-Monitors and/or user programs and external RAM mainly for program debugging. The /EA line enables/disables the internal flash and performs the mappings shown in fig.7 and fig. 8.

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