SM59R16A5/SM59R09A5/SM59R05A5
8-Bit Micro-controller
64KB/36KB/20KB with ISP Flash
& 2KB RAM embedded
3.2. Data Memory
The SM59R16A5 has 2K + 256Bytes on-chip SRAM, 256 Bytes of it are the same as general 8052 internal memory
structure while the expanded 2KBytes on-chip SRAM can be accessed by external memory addressing method ( by
instruction MOVX.)
Fig 3-2 (a)：External memory access as read
Fig 3-2 (b)：External memory access as write
07FF
Expanded 2K Bytes
(Accessed by direct external
addressing mode by
FF
FF
80
instruction MOVX)
Higher 128 Bytes (Accessed by
indirect addressing mode only)
SFR (Accessed by direct addressing
mode only)
80
7F
Lower 128 Bytes (Accessed by direct
& indirect addressing mode )
0000
00
Fig. 3-3: RAM architecture
3.2.1. Data memory - lower 128 byte (00h to 7Fh)
Data memory 00h to FFh is the same as 8052.
The address 00h to 7Fh can be accessed by direct and indirect addressing modes.
Address 00h to 1Fh is register area.
Address 20h to 2Fh is memory bit area.
Address 30h to 7Fh is for general memory area.
Specifications subject to change without notice contact your sales representatives for the most recent information.
ISSFD-M047 24 Ver.G SM59R16A5 01/2014
SYNCMOS [ SYNCMOS TECHNOLOGIES,INC ]
