DS83C530-DS87C530 Datasheet, PDF (29/46 Pages) Maxim Integrated Products – EPROM/ROM Microcontrollers with Real-Time Clock

DS87C530/DS83C530 EPROM/ROM Microcontrollers with Real-Time Clock
Table 9. EPROM Programming Modes
MODE
RST PSEN ALE/PROG EA/VPP P2.6 P2.7 P3.3 P3.6 P3.7
Program Code Data
H
L
PL
12.75V L H H H H
Verify Code Data
H
L
H
H
L
L
L
H
H
Program Encryption
Array Address 0-3Fh
H
L
PL
12.75V L
H
H
L
H
Program Lock LB1 H
L
Bits
LB2 H
L
PL
12.75V H H H H H
PL
12.75V H
H
H
L
L
LB3 H
L
PL
12.75V H
L
H
H
L
Program Option
Register Address FCh
H
L
PL
12.75V L
H
H
L
L
Read Signature or
Option Registers 30,
H
L
H
31, 60, FCh
* PL indicates pulse to a logic low.
H
L
L
L
L
L
Table 10. EPROM Lock Bits
LOCK BITS
LEVEL
LB1 LB2 LB3
1
U
U
U
2
P
U
U
3
P
P
U
4
P
P
P
PROTECTION
No program lock. Encrypted verify if encryption table was
programmed.
Prevent MOVC instructions in external memory from reading
program bytes in internal memory. EA is sampled and latched on
reset. Allow no further programming of EPROM.
Level 2 plus no verify operation. Also, prevent MOVX instructions in
external memory from reading SRAM (MOVX) in internal memory.
Level 3 plus no external execution.
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