ST7093

Ver 2.1

2003/09/23

Character Generator ROM (CGROM)

The character generator ROM generates 5 x 8 dot character patterns from 8-bit character codes. It can generate

256 5 x 8 dot character patterns. User-defined character patterns are also available by mask-programmed ROM.

Character Generator RAM (CGRAM)

In the character generator RAM, the user can rewrite character patterns by program. For 5 x 8 dots, eight

character patterns can be written.

Write into DDRAM the character codes at the addresses shown as the left column of Table 4 to show the character

patterns stored in CGRAM.

See Table 5 for the relationship between CGRAM addresses and data and display patterns. Areas that are not

used for display can be used as general data RAM.

Timing Generation Circuit

The timing generation circuit generates timing signals for the operation of internal circuits such as

DDRAM, CGROM and CGRAM. RAM read timing for display and internal operation timing by MPU access are generated

separately to avoid interfering with each other. Therefore, when writing data to DDRAM, for example, there will be no

undesirable interference, such as flickering, in areas other than the display area.

LCD Driver Circuit

LCD Driver circuit has 26 common and 80 segment signals for LCD driving. Data from CGRAM/CGROM is

transferred to 80 bit segment latch serially, and then it is stored to 80 bit shift latch. When each common is

selected by 26 bit common register, segment data also output through segment driver from 80 bit segment latch.

Cursor/Blink Control Circuit

It can generate the cursor or blink in the cursor/blink control circuit. The cursor or the blink appears in the digit at

the display data RAM address set in the address counter.

Applicable Panel Size

Font

Display

Duty

Contents of outputs

2 Line X 16 Char

1/17

2x16 characters + 80icons

5X8

3 Line x 16 Char

1/25

3x16 characters + 80icons