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1 on-chip extended static ram (sram) – Texas Instruments MSC1210 User Manual

Page 30

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Data Memory

2-4

Table 2−2. Program and Data Memory Addresses.

HCR0

MSC1210Y2

MSC1210Y3

MSC1210Y4

MSC1210Y5

DFSEL

PM

DM

PM

DM

PM

DM

PM

DM

000 (reserved)

001

0000

0400-83FF

010

0000

0400-43FF

0000-3FFF

0400-43FF

011

0000

0400-23FF

0000-1FFF

0400-23FF

0000-5FFF

0400-23FF

100

0000

0400-13FF

0000-0FFF

0400-13FF

0000-2FFF

0400-13FF

0000-6FFF

0400-13FF

101

0000-07FF

0400-00BF

0000-17FF

0400-0BFF

0000-37FF

0400-0BFF

0000-77FF

0400-0BFF

110

0000-00BF

0400-07FF

0000-1BFF

0400-07FF

0000-3BFF

0400-07FF

0000-7BFF

0400-07FF

111 (default)

0000-0FFF

0000

0000-1FFF

0000

0000-3FFF

0000

0000-7FFF

0000

Note:

Program accesses above the highest listed address will access external Program memory.

Program memory addressing beyond the on-chip address range is accessed
externally via ports 0 and 2. The total amount of code memory, on-chip and off,
is limited to 64k due to limitations of the 8052 architecture.

Note:

MSC1210 programs are limited to 64k because code memory is restricted to
64k. Some compilers offer ways to get around this limit when used with specially
wired hardware. However, without such special compilers and hardware, pro-
grams are limited to 64k.

The MSC1210 includes 2k of boot ROM code that controls operation during
serial or parallel programming. In program mode, the boot ROM is located in
the first 2kB of program memory.

The boot ROM is available to your program as long as EBR (hardware configu-
ration register 0, bit 4) is set, which is the default. When enabled, the boot ROM
routines will be located at program memory addresses F800

H

-FFFF

H

. The

boot ROM includes a number of functions such as flash memory access, and
serial routines including data transmission, reception, and auto-baud.

2.3

Data Memory

Data memory is divided into four types of memory, depending on its location
and volatility: internal RAM, on-chip extended SRAM, off-chip external SRAM,
and on-chip flash data memory. However, data memory (regardless of its loca-
tion or volatility) is accessed using the MOVX instruction, except for internal
RAM, which is accessed using the MOV instruction.

2.3.1

On-Chip Extended Static RAM (SRAM)

The MSC1210 includes 1024 bytes of on-chip extended static RAM (SRAM).
Even though this memory resides on-chip, it is accessed using the MOVX instruc-
tion as if it were external data memory. Whenever a program accesses data
memory addresses 0000

H

through 03FF

H

, the on-chip external SRAM is used.