24

AT89LS52

2601A–12/01

Programming Interface – Parallel Mode

Every code byte in the Flash array can be programmed by using the appropriate combination of control signals. The write

operation cycle is self-timed and once initiated, will automatically time itself to completion.

All major programming vendors offer worldwide support for the Atmel microcontroller series. Please contact your local pro-

gramming vendor for the appropriate software revision.

Notes:

1. Each PROG pulse is 200 ns - 500 ns for Chip Erase.

2. Each PROG pulse is 200 ns - 500 ns for Write Code Data.

3. Each PROG pulse is 200 ns - 500 ns for Write Lock Bits.

4. RDY/BSY signal is output on P3.0 during programming.

5. X = don’t care.

Table 10. Flash Programming Modes

Mode

V

CC

RST

PSEN

ALE/

PROG

EA/

V

PP

P2.6

P2.7

P3.3

P3.6

P3.7

P0.7-0

Data

P2.4-0

P1.7-0

Address

Write Code Data

5V

H

L

(2)

12V

L

HHHH

D

IN

A12-8

A7-0

Read Code Data

5V

H

L

H

H

L

L

L

H

H

A12-8

A7-0

Write Lock Bit 1

5V

H

L

(3)

12V

HHHHH

X

X

X

Write Lock Bit 2

5V

H

L

(3)

12V

H

H

H

L

L

X

X

X

Write Lock Bit 3

5V

H

L

(3)

12V

H

L

H

H

L

X

X

X

Read Lock Bits

1, 2, 3

5V

H

L

H

H

H

H

L

H

L

P0.2,

P0.3,

P0.4

XX

Chip Erase

5V

H

L

(1)

12V

H

L

H

L

L

X

X

X

Read Atmel ID

5V

H

L

H

H

LLLLL

1EH

X 0000

00H

Read Device ID

5V

H

L

H

H

LLLLL

62H

X 0001

00H

Read Device ID

5V

H

L

H

H

LLLLL

06H

X 0010

00H