70

DATA[7:0]

DATA

This 8-bit data message writes the data at the location indicated by the write pointer. The 4-bit data MSB

is copied from the last previous 16-bit data message.

The 0-bit data message writes a data at the location indicated by the write pointer. The last data is used

from the previous 8-bit or 16-bit data message.

15

12

11

0

0010

don’t care

CONTROL

This 16-bit control message stops the 4*fsc quartz oscillator.

15

12

11

0

0011

don’t care

CONTROL

This 16-bit control message resets the circuit and starts the 4*fsc quartz oscillator. This message should

not be used if an external 4 x fsc clock is used instead of the quartz. It is mandatory that reset operation is

as described in paragraph 2.3.

DATA

CLK

CSN

DATA

CLK

CSN

DATA

CLK

CSN

15

14

13

12

2

1

0

7

6

54

3210

16-BIT

MESSAGE

8-BIT

MESSAGE

0-BIT

MESSAGE

Figure 2

2.2 - The Write Pointer

As described in the ”message format” paragraph,

an address consists of three fields : STRU[7:6],

BUF[11:8], DEPL[4:0].

The STRU[7:6] field indicates whether it is a PAGE

address or a ROW ATTRIBUTE / REGISTER ad-

dress. It also determines the address incrementa-

tion scheme.

- STRU[7:6] = 00 :

It is a PAGE address. BUF provides the row

number (from 0 to 10) and DEPL provides the

character number (from 0 to 27). DEPL is incre-

mented after each data message. When the write

of a row is completed, the write pointer is auto-

matically set to the next row first character.

- STRU[7:6] = 01 :

It is also a PAGE address but the incrementation

scheme is a bit different : when the write of a row

is completed, the write pointer is automaticallyset

to the first character of the same row.

- STRU[7:6] = 11 :

It is a row attribute or a register address. The BUF

field must be set to 0000 and the DEPL field is

incremented after each data access.

STV5730

11/19