Memory
Organization
00-7F
RAM, Access it via direct addressing
SFR, Access it via direct addressing
80-FF
80-FF
indirect on-chip RAM,
Access it via indirect addressing
00-FF
00-
on-chip expanded RAM (256B),
Access it via MOVX instruction
off-chip memory, enabled by setting ERAM=1
Address Space for MPC89x51A RAM
0000-0FFF Program Memory (4KB)
1000-3BFF
NonVolatile data memory
shared with ISP program
memory.
ISP program could take
1KB, 2KB or 4KB
depending on OR0[5:4]
Address Space for MPC89x51A embedded Flash memory
Bits-7
Bits-6
Bits-5
Bits-4
Bits-3
-
Bits-2
Bits-1
SB
Bits-0
LOCK
ISPAS1
ISPAS0
MOVCL
Non-volatile register OR0
7
6
5
4
3
2
1
0
FZWDTCR
OSCDN
HWBS
EN6T
Non-volatile register OR1
MEGAWIN
MPC89x51A Data Sheet
9