hd66765 Renesas Electronics Corporation., hd66765 Datasheet - Page 53

• Manufacturer Part Number: hd66765
• Description: 396-channel Segment Driver With Internal Ram For 4096-color Displays - Hitachi Semiconductor
• Manufacturer: Renesas Electronics Corporation.

4. Write mode 4: AM = 1, LG2–0 = 110/111
Operation Examples:
This mode is used when a vertical comparison is performed between the write data and the set value
of the compare register (CP11–0) to write the data. When the result by the comparison in a byte unit
satisfies the condition, the write data sent from the microcomputer is written to the GRAM. In this
operation, the write-data mask function (WM11–0) are also enabled. After writing, the address
counter (AC) automatically increments by 256, and automatically jumps to the upper-right edge (I/D
= 1) or upper-left edge (I/D = 0) following the I/D bit after it has reached the lower edge of the
GRAM.
1) I/D = "1", AM = "1", LG2-0 = "111" (unmatched write)
2) CP11—0 = "530"H
3) WM11—0 = "000"H
4) AC = "0000"H
Write-data mask:
Compare register:
Write data (1):
Write data (2):
"0000"H
"0001"H
"AF00"H
1 0 0 1 1 0 0 1 1 0 0 1
* * * * * * * * * * * *
DB11
DB11
0
0
1 0 0 1 1 0 0 1 1 0 0 1
0 1 0 1 0 0 1 1 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0
1 0 1 0 0 1 1 0 0 0 0
Figure 39 Writing Operation of Write Mode 4
(Unmatched)
(Matched)
GRAM
Write data (1)
DB0
DB0
53
Compare
operaton
Compare
operaton
C
C
Conditional
replacement
Conditional
replacement
R
R
1 0 0 1 1 0 0 1 1 0 0 1
* * * * * * * * * * * *
HD66765