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3.19.3 VP_MAP Translation

The MCU, which has an MMU, translates internal addresses (virtual addresses) to actual memory

addresses (physical addresses). Address translation is performed according to the address

translation table (translation look-aside buffer: TLB) in the MCU. The MMU operates during

command input wait state as well as during user program execution. When a command for

memory access is executed while the MMU address translation function is enabled, the address

translated by the MMU is accessed. If the specified address is not within the TLB, a TLB miss

occurs, and the TLB must be updated by the user program.

The emulator has address translation functions according to the VP_MAP tables. The VP_MAP

tables are the address translation tables for the emulator created with the VPMAP_SET command.

The following shows an example of how to use the VP_MAP tables.

Example:

1. Create VP_MAP tables for translating virtual addresses H'10000 to H'10FFF to physical

addresses H'4000000 to H'4000FFF and virtual addresses H'11000 to H'11FFF to physical

addresses H'0 to H'FFF.

>vs 10000 10FFF 4000000 (RET)

>vs 11000 11FFF 0 (RET)

>vd (RET)

<VADDR_TOP> <VADDR_END> <PADDR_TOP>

00010000 00010FFF 04000000

00011000 00011FFF 00000000

DISABLE

2. Then, enable the VP_MAP tables. (When the tables are disabled, addresses are not translated.)

>ve ;enable (RET)

>vd (RET)

<VADDR_TOP> <VADDR_END> <PADDR_TOP>

00010000 00010FFF 04000000

00011000 00011FFF 00000000

ENABLE

Here, virtual addresses correspond to physical addresses as shown in figure 3.58.

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Renesas SH7641 Technical Information Seite 101