DisplayDataRAM(DDRAM)

The Display data RAM (DDRAM) stores display data represented in 8-bit character codes. Its extended capacity is

80

´8 bits or 80 characters. The area in the DDRAM that is not used for display can be used as general data RAM. Refer

to DDRAM addresstablefortherelationshipsbetween DDRAM addressandpositionsontheVFD.

The DDRAM address(ADD)issetintheaddresscounter(AC)ashexadecimal.

DDRAM AddressTable

HighOrderBits

LowOrderBits

AC6

AC5

AC4

AC3

AC2

AC1

AC0

Hexadecimal

Hexadecimal

Example: DDRAM address

²3FH²

0

1

1

1

1

1

1

3

F

DisplayPosition

(Digit)

1

2

3

4

5

6

79

80

DDRAM Address

00

01

02

03

04

05

4E

4F

(Hexadecimal)

When there are fewer than 80 display characters, the display begins at the head position. For example, if using only

one HT16528, 24 characters are displayed. When display shift operation is performed, the DDRAMaddress shifts as

showninthefollowingtable.

Example:1-lineby24-characterDisplayTable

DisplayPosition

(Digit)

1

2

3

4

5

6

23

24

DDRAM Address

00

01

02

03

04

05

16

17

(Hexadecimal)

ForShiftLeft

01

02

03

04

05

06

17

18

ForShiftRight

4F

00

01

02

03

04

15

16

HT16528

Rev.1.10

21

July5,2011