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

H

L

PL

12.75V

L

H

H

L

H

Array Address 0-3Fh

 

 

 

 

 

 

 

 

 

Program Lock

LB1

H

L

PL

12.75V

H

H

H

H

H

Bits

 

 

 

 

 

 

 

 

 

 

 

 

LB2

H

L

PL

12.75V

H

H

H

L

L

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

LB3

H

L

PL

12.75V

H

L

H

H

L

 

 

 

 

 

 

 

 

 

 

 

 

Program Option

 

H

L

PL

12.75V

L

H

H

L

L

Register Address FCh

 

 

 

 

 

 

 

 

 

Read Signature or

 

H

L

H

H

L

L

L

L

L

Option Registers 30,

31, 60, FCh

 

 

 

 

 

 

 

 

 

 

*PL indicates pulse to a logic low.

Table 10. EPROM Lock Bits

LEVEL

 

LOCK BITS

 

PROTECTION

 

 

 

 

 

LB1

 

LB2

 

LB3

 

 

 

 

 

 

 

 

 

 

 

1

U

 

U

 

U

No program lock. Encrypted verify if encryption table was

 

 

programmed.

 

 

 

 

 

 

2

P

 

U

 

U

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.

3

P

 

P

 

U

Level 2 plus no verify operation. Also, prevent MOVX instructions in

 

 

external memory from reading SRAM (MOVX) in internal memory.

 

 

 

 

 

 

4

P

 

P

 

P

Level 3 plus no external execution.

 

 

 

 

 

 

 

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