21

0850C–MICRO–3/06

AT89LS8252

Flash and EEPROM Parallel Programming Modes

Notes:

1. “h” = weakly pulled “High” internally.

2. Chip Erase and Serial Programming Fuse require a 10-ms PROG pulse. Chip Erase needs to be performed first before

reprogramming any byte with a content other than FFH.

3. P3.4 is pulled Low during programming to indicate RDY/BSY.

4. “X” = don’t care

Mode

RST

PSEN

ALE/PROG

P2.6

P2.7

P3.6

P3.7

Data I/O

P0.7:0

Address

P2.5:0 P1.7:0

Serial Prog. Modes

H

h (1)

h (1)

x

Chip Erase

H

L

(2)

12V

H

L

L

L

X

X

Write (10K bytes) Memory

H

L

12V

L

H

H

H

DIN

ADDR

Read (10K bytes) Memory

H

L

H

12V

L

L

H

H

DOUT

ADDR

Write Lock Bits:

H

L

12V

H

L

H

L

DIN

X

Bit - 1

P0.7 = 0

X

Bit - 2

P0.6 = 0

X

Bit - 3

P0.5 = 0

X

Read Lock Bits:

H

L

H

12V

H

H

L

L

DOUT

X

Bit - 1

@P0.2

X

Bit - 2

@P0.1

X

Bit - 3

@P0.0

X

Read Atmel Code

H

L

H

12V

L

L

L

L

DOUT

30H

Read Device Code

H

L

H

12V

L

L

L

L

DOUT

31H

Serial Prog. Enable

H

L

(2)

12V

L

H

L

H

P0.0 = 0

X

Serial Prog. Disable

H

L

(2)

12V

L

H

L

H

P0.0 = 1

X

Read Serial Prog. Fuse

H

L

H

12V

H

H

L

H

@P0.0

X