6

3378M–SEEPR–7/08

AT93C56A/66A

Note:

The X’s in the address field represent don’t care values and must be clocked.

Table 3-4.

Instruction Set for the AT93C56A and AT93C66A

Instruction

SB

Op

Code

Address

Data

Comments

x 8

x 16

x 8

x 16

READ

1

10

Reads data stored in memory, at

specified address.

EWEN

1

00

11XXXXXXX

11XXXXXX

Write enable must precede all

programming modes.

ERASE

1

11

WRITE

1

01

ERAL

1

00

10XXXXXXX

10XXXXXX

Erases all memory locations. Valid

WRAL

1

00

01XXXXXXX

01XXXXXX

D

D

Writes all memory locations. Valid

only at V

Register cleared.

EWDS

1

00

00XXXXXXX

00XXXXXX

Disables all programming instructions.