SyncMOS Technologies Inc.
September 2002
SM8958A
Extension Function Description
1. Memory Structure
The SM8958A is the general 8052 hardware core as a single chip micro controller. Its memory structure follows general 8052
structure.
1.1 Program Memory
The SM8958A has 32K byte on-chip flash memory which used as general program memory. The address range for the 32K
byte is $0000 to $7FFF.
7FFF
32K Program
memory space
0000
Note: The single flash block address structure for doing as well as program ROM flash.
1.2 Data Memory
The SM8958A has 1K bytes on-chip RAM, 256 bytes of it are the same as general 8052 internal memory structure while the
expanded 768 bytes on-chip RAM can be accessed by external memory addressing method (by instruction MOVX), or by
‘Bank mapping direct addressing mode’ as described in next page.
02FF
Expanded 768 bytes RAM
(Accessed by direct external
addressing mode, by instruction
MOVX, or by Bank mapping
direct addressing mode)
FF
FF
Higher 128 bytes (Access by
7F
00
80
indirect addressing mode only)
SFR (Accessed by direct
addressing mode only)
80
( OME = 1 )
Lower 128 bytes (Accessed by
direct & indirect addressing mode)
0000
On-chip expanded RAM address structure.
Specifications subject to change without notice,contact your sales representatives for the most recent information.
6/25
Ver 1.0
PID 8958A 09/02
SYNCMOS [ SYNCMOS TECHNOLOGIES,INC ]
