FD2000

Rev1.0

9/37

6. BLOCK FUNCTIONS

6.1. AC (ADDRESS COUNTER)

AC is a counter that provides the addresses used for DCRAM and ADRAM.

The address is automatically modified internally, and the LCD display state is retained.

6.2. DCRAM (DATA CONTROL RAM)

DCRAM is RAM that is used to store display data expressed as 8-bit character codes. (These character codes are

converted to 5 x 7, 5 x 8, or 5 x 9 dot matrix character patterns using CGROM or CGRAM.) DCRAM has a

capacity of 48 x 8 bits, and can hold 48 characters. The table below lists the correspondence between the 6-bit

DCRAM address loaded into AC and the display position on the LCD panel.

− When the DCRAM address loaded into AC is 00H.

Display digit

1

2

3

4

5

6

7

8

9

10

11

12

DCRAM address(HEX)

00

01

02

03

04

05

06

07

08

09

0A

0B

However, when the display shift is performed by specifying MDATA, the DCRAM address shifts as shown below.

Display digit

1

2

3

4

5

6

7

8

9

10

11

12

DCRAM address(HEX)

01

02

03

04

05

06

07

08

09

0A

0B

0C

(Left shift)

Display digit

1

2

3

4

5

6

7

8

9

10

11

12

DCRAM address(HEX)

2F

00

01

02

03

04

05

06

07

08

09

0A

(Right shift)

NOTE: The DCRAM addresses are expressed in hexadecimal.

LSB

MSB

DCRAM address

DA0

DA1

DA2

DA3

DA4

DA5

←

HEX

→

← HEX →

−

Example: When the DCRAM address is 2EH.

LSB

MSB

DA0

DA1

DA2

DA3

DA4

DA5

0

1

1

1

0

1

NOTE: 5 x 7 dots ... 12-digit display

5 x 7 dots

5 x 8 dots ... 12-digit display

4 x 8 dots

5 x 9 dots ... 12-digit display

3 x 9 dots